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Chronology of computation of π

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The table below is a brief chronology of computed numerical values of, or bounds on, the mathematical constant π. See the history of numerical approximations of π for explanations, comments and details concerning some of the calculations mentioned below.

Date</th> Who</th> Value of π
(world records in bold)
20th century BCEgyptian Rhind Mathematical Papyrus(16/9)² = 3.160493...
19th century BCBabylonians25/8 = 3.125
12th century BCChinese3
9th century BCIndian Shatapatha Brahmana339/108 = 3.138888...
434 BCAnaxagoras attempted to square the circle with compass and straightedge 
c. 250 BCArchimedes223/71 < π < 22/7
(3.140845... < π < 3.142857...)
20 BCVitruvius25/8 = 3.125
130Chang Hong√10 = 3.162277...
150Ptolemy377/120 = 3.141666...
250Wang Fan142/45 = 3.155555...
263Liu Hui3.141014
480Zu Chongzhi3.1415926 < π < 3.1415927
499Aryabhata62832/20000 = 3.1416
640Brahmagupta√10 = 3.162277...
800Al Khwarizmi3.1416
1150Bhaskara3.14156
1220Fibonacci3.141818
All records from 1400 onwards are given as the number of correct decimal places (dps).
1400Madhava of Sangamagrama discovered the infinite power series expansion of π11 dps
13 dps
1424Jamshid Masud Al Kashi 16 dps
1573Valenthus Otho 6 dps
1593François Viète 9 dps
1593Adriaen van Roomen 15 dps
1596Ludolph van Ceulen 20 dps
1615 32 dps
1621Willebrord Snell (Snellius), a pupil of Van Ceulen 35 dps
1665Isaac Newton 16 dps
1699Abraham Sharp 71 dps
1700Seki Kowa 10 dps
1706John Machin 100 dps
1706William Jones introduced the Greek letter 'π' 
1730Kamata 25 dps
1719De Lagny calculated 127 decimal places, but not all were correct 112 dps
1723Takebe 41 dps
1739Matsunaga 50 dps
1748Leonhard Euler used the Greek letter 'π' in his book Introductio in Analysin Infinitorum and assured its popularity. 
1761Johann Heinrich Lambert proved that π is irrational 
1775Euler pointed out the possibility that π might be transcendental 
1789Jurij Vega calculated 140 decimal places, but not all are correct 137 dps
1794Adrien-Marie Legendre showed that π² (and hence π) is irrational, and mentioned the possibility that π might be transcendental. 
1841Rutherford calculated 208 decimal places, but not all were correct 152 dps
1844Zacharias Dase and Strassnitzky 200 dps
1847Thomas Clausen 248 dps
1853Lehmann 261 dps
1853Rutherford 440 dps
1855Richter 500 dps
1874William Shanks took 15 years to calculate 707 decimal places, but not all were correct (the error was found by D. F. Ferguson in 1946) 527 dps
1882Lindemann proved that π is transcendental (the Lindemann-Weierstrass theorem) 
1897The U.S. state of Indiana came close to legislating the value of 3.2 (among others) for π. House Bill No. 246 passed unanimously. The bill stalled in the state Senate due to a suggestion of possible commercial motives involving publication of a textbook. More detail can be found at http://www.cs.uu.nl/wais/html/na-dir/sci-math-faq/indianabill.html.  
1910Srinivasa Ramanujan finds several rapidly converging infinite series of π, which can compute 8 decimal places of π with each term in the series. Since the 1980s, his series have become the basis for the fastest algorithms currently used by Yasumasa Kanada and the Chudnovsky brothers to compute π.
1946 D. F. Ferguson (using a desk calculator) 620 dps
1947 710 dps
1947 808 dps
1949 Ferguson and John W. Wrench, using a desk calculator 1,120 dps
All records from 1949 onwards were calculated with electronic computers.
1949 J. W. Wrench, Jr, and L. R. Smith were the first to use an electronic computer (the ENIAC) to calculate π (it took 70 hours) (also attributed to Reitwiesner et al) 2,037 dps
1953Kurt Mahler showed that π is not a Liouville number 
1954 Jeenel Nicholson, using the NORC (it took 13 minutes) 3,089 dps
1957 Felton, using the Ferranti Pegasus computer (London) 7,480 dps
1958 Genuys, using an IBM 704 (1.7 hours) 10,000 dps
1958 Felton, using the Pegasus computer (London) (33 hours) 10,021 dps
1959 Guilloud, using the IBM 704 (Paris) (4.3 hours) 16,167 dps
1961 IBM 7090 (London) (39 minutes) 20,000 dps
1961 Daniel Shanks and John W. Wrench, using the IBM 7090 (New York) (8.7 hours) 100,000 dps
1966 J. Guilloud and J. Filliatre, using the IBM 7030 (Paris) (taking 28 hours??) 250,000 dps
1967 Guilloud and Dichampt, using the CDC 6600 (Paris) (28 hours) 500,000 dps
1974 Guilloud and Bouyer, using the CDC 7600 1,000,000 dps
1981 Yasumasa Kanada and Kazunori Miyoshi, FACOM M-200 2,000,036 dps
1983 Yasumasa Kanada and Yasunori Ushiro, HITAC S-810/20 10,013,395 dps
1987 Yasumasa Kanada, Yoshiaki Tamura, Yoshinobu Kubo, NEC SX-2 134,214,700 dps
1989 G.V. Chudnovsky & D.V. Chudnovsky, IBM 3090 535,339,270 dps
1989 Yasumasa Kanada and Yoshiaki Tamura, HITAC S-810/20 536,870,898 dps
1989 G.V. Chudnovsky & D.V. Chudnovsky, IBM 3090 1,011,196,691 dps
1989 Yasumasa Kanada and Yoshiaki Tamura, HITAC S-810/20 1,073,740,799 dps
1995 Yasumasa Kanada and Daisuke Takahashi, HITAC S-3800/480 (dual CPU) 6,442,450,000 dps
1997 Yasumasa Kanada and Daisuke Takahashi, HITACHI SR2201 (1024 CPU) 51,539,600,000 dps
1999 Yasumasa Kanada and Daisuke Takahashi, HITACHI SR8000/MPP (128 nodes) 206,158,430,000 dps
2002 Yasumasa Kanada & team, HITACHI SR8000/MPP (64 nodes), 600 hours 1,241,100,000,000 dps

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