Number of active users of bitcoin in 2019
The total number of bitcoins is 21 million
in 2009, when bitcoin was born, block reward was 50 bitcoins. Ten minutes after its birth, the first 50 bitcoins were generated, and the total amount of money at this time is 50. Then bitcoin grew at a rate of about 50 every 10 minutes. When the total amount reaches 10.5 million (50% of 21 million), the block reward will be halved to 25
when the total amount reaches 15.75 million (5.25 million new output, i.e. 50% of 1050), the block reward will be further halved to 12.5. The monetary system used to have no more than 10.5 million in four years, after which the total number will be permanently limited to about 21 million
extended data
monetary characteristics
1. Decentralization: bitcoin is the first distributed virtual currency, and the whole network is composed of users without a central bank. Decentralization is the guarantee of bitcoin's security and freedom
2. Global circulation: bitcoin can be managed on any computer connected to the Internet. No matter where you are, anyone can dig, buy, sell or collect bitcoin
3. Exclusive ownership: private key is needed to control bitcoin, which can be stored in any storage medium in isolation. No one can get it except the user himself
4. Low transaction cost: bitcoin can be remitted free of charge, but a transaction fee of about 1 bitfen will be charged for each transaction to ensure faster transaction execution
5, no hidden cost: as a means of payment from a to B, bitcoin has no cumbersome limit of quota and proceres. If you know the other party's bitcoin address, you can pay
6. Cross platform mining: users can explore the computing power of different hardware on many platforms
Since last weekend, BTC has soared all the way from 6400 on Friday to 7500. Today, it has exceeded 8000 US dollars. This surge caught the masses off guard and made investors ecstatic
2019 can be described as a "prosperous" year for bitcoin. It is strong enough to get rid of the downward trend in 2018 and usher in a recovery. It has broken through 6000 points, 6400 points, 6800 points and other barriers one after another, and even reached $8000, making the coin circle return to its long lost heat
BTC is also in the focus of social media. Let's explore the reasons behind the boom:
the rise of bitcoin is not so much a sudden "earthquake" as a long-term "storm"
first of all, bitcoin immediately ushers in the practice of recing proction once every four years, which will inevitably lead to an increase in the price of bitcoin. Second, fidelity, the world's largest asset management company, joined the ranks of bitcoin investors in May. Compared with traditional investments such as gold and oil, bitcoin has achieved an average return of 457% in the past two years, making traditional financial giants ready to move
in January this year, the US Congress discussed two bills on virtual currency, and bitcoin futures ETF returned to the public view. However, the market failure of usdt currency makes a large number of users of usdt into the embrace of BTC
of course, President trump of the United States is the only culprit. Since then, trump has decided to raise China's export tariff from 10% to 25%. China's export instry is facing a disaster. The domestic stock market has plummeted, and hot money has flowed into the cryptocurrency market from the stock market, which has contributed to the surge of the comparative currency< Bitoffer revealed that bitcoin may return to its peak
according to the COO of bitoffer of Singapore sto exchange, the price of bitcoin has returned to last April's level, and it is predicted that it will exceed US $100000 this year<
45% of the respondents believe that when BTC reaches $10000, there will be fomo effect
Tom Lee, co-founder of fundstrat, launched a questionnaire on twitter about "what price BTC will have fomo effect". Up to now, the survey data shows that 32% of the people think that when the BTC exceeds $20000 (a new high), the BTC will be the highest; 45% thought that when the BTC reached $10000; 23% think it's now
bitoffer is a cryptocurrency exchange from Singapore STO, which provides secure and reliable bitcoin trading and asset management services for millions of users in more than 100 countries< br />
Let's start with a simple conclusion: a year ago, the data showed that there were about 500000 BTC
two American brothers, Cameron winkleworth and Taylor winkleworth, claiming that they owned 1% of bitcoin [1] 1% of the world's bitcoin? At present, the total amount of bitcoin in the world is about 12 million, that is to say, the two brothers hold about 120000 bitcoins< maybe you don't think it's worth much, but note that the starting price of bitcoin for these two people is less than $10 / bitcoin
Please note that entities are used instead of people. In the analysis method of this paper, bitcoin wallets that may belong to the same owner are divided into the same entity, which may be not only a person, but also a trading organization like Mt. GOx in addition, through the analysis of the most active entity table given in this paper, the income of the people with the most income (excluding expenses) is less than 700000 BTC. In other words, the person with the most bitcoin will hold no more than 700000 bitcoins. How many people in the world own bitcoins? The paper concludes that as of May 13, 2012, 1.85 million entities hold bitcoin. If we assume that bitcoin users have grown linearly since the advent of bitcoin (January 2009), the current number should be 2.5 million. Because the number of entities is counted on paper, the actual number of bitcoin holders should be a little less than this number, but not much smaller, because after all, there are not many large trading platforms
In addition to the above two problems, [3] also gives many interesting conclusions, such as: < UL >about 55% of bitcoin can be saved without money
in places like GOx mountain, almost all deals are small ones
before May 2012, almost all large single transactions (& gt; 50000 BTC) are subsequent transactions of 90000 BTC on November 8, 2011. There are very strange patterns in this long list of transactions. For example, an entity divides 90000 BTCs into different sizes, sends them back to itself three times, and then sells them on Mt. GOx. 90000 BTCs sold are sent back to the entity through 90 different bitcoin addresses, with 1000 bitcoins per address. These operations indicate that the entity appears to be trying to hide the relationship between these transactions
bitcoin miners will mine 18 million bitcoins this week, and only the remaining 3 million bitcoins will be released before mining stops in 2140 commentators said at the time that the motivation of hoarding bitcoin came from the curiosity in technology. In view of the current price of BTC / USD, financial incentives reverse the activity of bitcoin hoarding by holders in 2019< br />
bitcoin is a virtual currency system developed by an organization that dare not disclose its identity. Also known as "air currency"
this kind of currency is worthless. We should rely on pyramid selling and speculation to improve the psychological value among a small number of people, then buy and sell among these people, and then continue to rely on pyramid selling to expand the population
this is a financial fraud, much like the Ponzi scheme
as long as people who are not mentally retarded, they should be aware that this is a fraud
it's just that people who speculate in currency think that they won't be the last one to take over the dish.
changing the mining point does not help to improve the speed, only rely on the RMB props
miner's pick and amulet to improve the speed
Level 3 anonymous digging can
pay attention to squatting a mining point with others may affect the speed
1-75: copper mine will be found in the birthplace
75-125: segenite in wetland, tin ore and igneous ore (in spider hole)
125-175: alx highland, Nano iron mine (walking along the mountains)
175-245: there are two choices
① in the three holes of Filas: each hole basically has 3-4 secret silver
② it is mainly concentrated in the east of the wilderness, where there are JY Dragons: there are iron, secret silver and real silver
you can practice until 245
245: go to the fat man hole above LM stronghold, there are black iron, Se silver and secret silver, A lot of them have been trained until 275
275: you can dig fuser silver and start to make money. Ha ha
there are also two choices
①: East plague, there are five points to brush fuser silver on the Internet, And the chance of getting out of arcane crystal is high
②: go to the hole of the three JY worms in xlss (LR DZ small D is recommended) and each of them has 4-6 fuser silver
after 300, you can mix in Outland to 375!
Nakamoto's mining is unreliable
On October 31, 2008, a person named Nakamoto published a research report called bitcoin: a peer-to-peer cash payment system on a secret cryptography discussion group, which elaborated the new idea of e-moneysoon after, he developed an operating system for bitcoin issuing, trading and account management on the platform of P2P (peer-to-peer or person to person) peer-to-peer network and distributed database, combining the working mode of open source software and block cipher in cryptography
the system enables all nodes throughout the peer-to-peer network to reach network agreements according to their seed files, so as to ensure fairness, security and reliability in currency issuance, management and circulation
after the advent of bitcoin, it quickly attracted the following and attention of geeks. However, what is puzzling is that after leaving bitcoin in cyberspace, Nakamoto Tsung has not been as frequently active in the bitcoin community as before, but graally faded out of the public's sight
in the spring of 2011, after leaving behind the sentence "I started to do something else", Nakamoto completely evaporated from the Internet space. No one can know his real identity, only that this mysterious figure left 2 million bitcoins for himself in the earliest block he owned, and these bitcoins have not been passive yet
people want to see the true face of Nakamoto, and even use the powerful human flesh search tool to search, which is still fruitless, Even the two Google engineers who later took charge of repairing the bitcoin project claimed that they had never found and met Nakamoto at the scene
extended data mining is a process of increasing bitcoin money supply. Mining also protects the security of the bitcoin system, prevents fraulent transactions, and avoids "double payment", which means spending the same bitcoin multiple times
miners provide algorithms for bitcoin network in exchange for the opportunity of bitcoin reward. The miners verify each new transaction and record it in the general ledger
every 10 minutes, a new block will be "mined", and each block contains all the transactions from the generation of the previous block to the present, which are added to the blockchain in turn
we call the transactions included in the block and added to the blockchain "confirmed" transactions. Only after the transaction is "confirmed" can the new owner spend the bitcoin he gets in the transaction
in this paper, I would like to talk about some superficial understanding of this problem< First, we should fully understand the importance of developing computing ability
one of the aims of primary school mathematics teaching is to cultivate students' computational ability, and teachers must have enough understanding. Some teachers don't pay enough attention to the cultivation and improvement of students' computing ability, and they don't let students find the rules and interests of computing. This is a big obstacle to cultivate and improve students' computing ability, which must be removed. Computational ability is a necessary ability for students< Number and calculation are widely used in daily life, work and study. In the real world, from the perspective of mathematics, there are mainly three aspects: number, quantity and shape. However, measurement is inseparable from number and calculation, and the quantification of body size is inseparable from number and calculation. Therefore, number and calculation are the most basic tools for people to understand the objective world and the basic knowledge and skills that every citizen should master< Number and calculation are the basis for students to learn other mathematical knowledge and even other subjects. This part of the knowledge is not good, students can not enter the normal learning< Number and calculation play an important role in cultivating students' thinking ability. Mastering the process of number and calculation is also the process of cultivating students' abstract generalization ability. In this way, students also develop the ability of abstract generalization in the process of learning to master the knowledge of number and calculation
4. The teaching of number and calculation is concive to infiltrating the enlightenment ecation of dialectical materialism. The concept of number is graally formed and developed with the needs of human life and practice. When teachers want to teach the concept of number, the relationship between calculation method and calculation method, they can infiltrate the enlightenment ecation of dialectical materialism
Second, clarify the calculation theory and improve the teaching quality of calculation
in the teaching of calculation, teachers should pay attention to explain the principle of calculation and reveal the law of calculation, so that students can know what it is and why it is
1. The abstraction of arithmetic is a difficult point in primary school teaching. In teaching, we try to transform the abstraction into the concrete by means of visual demonstration, so as to make the arithmetic clear
2. Learn to operate with tools, explore and comprehend. Psychologists believe that thinking begins with action. To enable students to master mathematical knowledge and promote the development of thinking, it is necessary to build a bridge between image thinking and mathematical abstraction, and give full play to the role of learning tools. For example, if the students have difficulty in understanding the "method of making up ten" in addition within 20, we will ask them to come out with sticks to help them learn the calculation method of "making up ten" by playing with sticks
3. Contact with practice to deepen understanding. Using students' existing knowledge and experience to understand new knowledge is the main way to construct teaching knowledge structure. Properly using old knowledge in teaching, assimilating new knowledge through analogy, and realizing positive transfer of knowledge are concive to students' understanding of new knowledge and recognition of new knowledge structure. For example, when teaching the calculation method of decimal addition, we can use the rate relationship of RMB units that students are familiar with to explain the reason that decimal points must be aligned
4. Pay attention to perception and strengthen stimulation. For the parts that are easy to be ignored by students, we should pay attention to strengthen the stimulation intensity (such as emphasis on entering and leaving places, emphasis on the treatment of decimal points, etc.) to attract students' attention, leave students a clear and correct impression, and avoid and rece errors in future calculation
5. According to the characteristics that students are prone to illusion and thinking set, we should consciously differentiate and compare the similar concepts, rules and formulas, so as to promote the accurate differentiation of new and old knowledge
6. Practice in time to consolidate and improve. Carry out targeted exercises, strengthen the key points and difficulties in the calculation process, and strive to consolidate in class
7. Pay attention to feedback and correct in time. Timely feedback, find out the students' mistakes, help students analyze the reasons and correct the mistakes in time< Third, we should deal with the relationship between written and oral arithmetic
oral arithmetic is a kind of calculation method which can only calculate and get the results by thinking and language without any tools. It has the characteristics of fast and flexible
mental arithmetic is an important part of computing power. Oral calculation is the basis of written calculation and estimation. Both written calculation and estimation ability are developed on the basis of accurate and skilled oral calculation ability. Without a certain basis of oral calculation, the cultivation of written calculation and estimation ability becomes the water without source. In addition, mental arithmetic is widely used in daily life, proction and scientific research. Therefore, it is very important to insist on the training of oral arithmetic and listening arithmetic in teaching to improve students' computing ability
(1) oral arithmetic teaching must run through the whole process of primary school mathematics teaching. In the lower grades, basic oral arithmetic such as addition and subtraction within 20, multiplication within the table and division are arranged; The middle grade arranges some oral arithmetic which is the basis of written arithmetic and often used in daily life; In order to cultivate students' ability of using knowledge flexibly and their ability of oral calculation, senior students arrange some questions of using operation law to do oral calculation in exercises. Each teaching reference book puts forward the requirements for the oral arithmetic of this semester in stages. Teachers should make the cultivation of oral arithmetic ability to be implemented, and effectively improve students' oral arithmetic ability
(2) arrange oral calculation reasonably. In compulsory textbooks, the basic oral arithmetic, which is the basis of written arithmetic, is taught before written arithmetic, while some difficult but not the most basic ones are taught after written arithmetic, so as to further improve students' oral arithmetic ability. For example, addition and subtraction within 20 is an important foundation of addition and subtraction, and only oral arithmetic is taught. In addition and subtraction within 100, two digit addition, subtraction of one digit and integral tens, such as 27 + 6, 27 + 30, are the basis of both written and oral arithmetic. Therefore, this part of the content before the written calculation, only teaching oral calculation; It is more difficult for students to master double-digit plus or minus double-digit, so the first grade first teaches written arithmetic, and the second grade further requires oral arithmetic. In this way, students can not only learn written arithmetic, but also form a strong ability of oral arithmetic
(3) pay attention to the teaching of oral arithmetic. Oral examples should pay attention to the intuitive demonstration and operation to make students understand the calculation theory
(4) teach students oral arithmetic and develop their thinking. In order to improve students' ability of oral arithmetic, we should teach students correct methods of oral arithmetic. The methods are various, and we should guide students to choose the methods that they can easily understand and master. Never guide students to do oral arithmetic with the method of written arithmetic. Two digit addition: 28 + 37. I find that some students think like this: 8 + 7 = 15, indivial digit is 5, ten digit is 2 + 3 + 1 = 6, ten digit is 6. This is completely the idea of written calculation. In fact, you should think like this: 28 + 30 = 58, 58 + 7 = 75. You don't need to have a vertical pattern in your head
practice has proved that strengthening the training of oral arithmetic can not only improve the calculation level of students, but also develop their thinking ability< Fourth, encourage students to use simple algorithms to improve their ability and develop their thinking
simple calculation is a practical and effective method to improve students' calculation speed. Simple calculation often uses certain operation laws, such as addition calculation often uses addition exchange law, addition combination law, and multiplication exchange law, multiplication combination law, multiplication distribution law, etc. in multiplication calculation, some calculations are simplified from complex to easy. The study of simple calculation can not only improve the students' calculation speed, rece the calculation errors, but also help the development of students' thinking. Therefore, in the teaching process, teachers should strengthen the teaching of simple methods
in addition, let students remember some common data, which can simplify the calculation process and improve the calculation speed. I remember an ecator said that a person's memory before the age of 13 is the best. He can remember a lot of things at this stage. Although he doesn't know why and how, these things don't affect his memory. The unknown reasons of these knowledge will be solved with the growth of his age and the increase of his knowledge. Therefore, we should pay attention to the development of students' memory, especially before the age of 13. The content of calculation in middle and high grades is extensive, comprehensive and comprehensive. Some common operations are often encountered in real life. These operations have no specific rules of oral arithmetic, and must be solved by strengthening memory training. The main contents of my intensive training are as follows: 1) the square result of each number from 1 to 10 in the natural number; ② A method of oral calculation for the square result of two digit number of 5 on a digit; ③ Some specific calculation results, such as 125 × 8＝1000，25 × 4 = 100, 0.25 =, 0.75 =, 0.125 =, 0.375 =, 0.625 = etc. These special calculation results are frequently used in practice, homework and life. If we master and remember them skillfully, we can transform them into abilities, which play a good role in calculation and proce high efficiency< 5. Pay attention to cultivate the good habit of careful examination and calculation
the teaching of calculation also needs to train students to form the habit of careful examination and examination. Don't just shout "be careful!" to students, To teach methods, strict requirements, form habits, improve the accuracy of calculation
the new curriculum standard points out that we should pay attention to the cultivation of students' habit of inspection. Inspection is a good way, it can make people find their own mistakes in time and correct them in time. In the process of teaching, teachers should pay attention to strengthen the teaching of checking calculation, let students use different methods to test a problem, master the test method, and skillfully use this method to judge the correctness of the answers to similar problems
six relations between addition, subtraction, multiplication and division are often used in checking. The estimation is often based on the variation of proct and quotient. For example: according to the multiplier & gt; 1, proct & gt; Multiplicand (except 0); Multiplier = 1, proct = multiplicand; If the multiplier is less than 1, the proct is less than the multiplicand (except 0), you can judge which of the following questions is greater than the multiplicand, which is less than the multiplicand, and which is equal to the multiplicand: 8 × 、 nine × 、 one × 2、0.9 × 16、5 × 1、3 × 、 × 1 According to divisor > 1, quotient < divisor (except 0); Divisor = 1, quotient = dividend; If the divisor is less than 1, the quotient is greater than the divisor (except 0), it can be judged without calculation ÷ 14、8 ÷ 1 、21 ÷ 、 ÷ 7、2 ÷ 1、0.45 ÷ Is the quotient greater than the divisor, less than the divisor, or equal to the divisor< Sixth, enrich learning activities, be happy with teaching and learning, and stimulate students' interest
the calculation problem is composed of numbers and abstract operation symbols, which makes students easily feel irritable and tired. Therefore, teachers should