Name William Shanks | Role Mathematician | |
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Born 25 January 1812Corsenside, Houghton-le-Spring, city of Sunderland, Tyne and Wear, England ( 1812-01-25 ) Fields Amateur calculator, school owner Died June 1882, Houghton-le-Spring, United Kingdom | ||
William Shanks (25 January 1812 – June 1882) was a British amateur mathematician.
Shanks is famous for his calculation of π to 707 places, accomplished in 1873, which, however, was only correct up to the first 527 places. This error was highlighted in 1944 by D. F. Ferguson (using a mechanical desk calculator).
Shanks earned his living by owning a boarding school at Houghton-le-Spring, which left him enough time to spend on his hobby of calculating mathematical constants. His routine was as follows: he would calculate new digits all morning; and then he would spend all afternoon checking his morning's work. To calculate π, Shanks used Machin's formula:
Shanks's approximation was the longest expansion of π until the advent of the electronic digital computer about one century later.
Shanks also calculated e and the Euler–Mascheroni constant γ to many decimal places. He published a table of primes up to 60 000 and found the natural logarithms of 2, 3, 5 and 10 to 137 places.
Shanks died in Houghton-le-Spring, County Durham, England in June 1882, aged 70, and was buried at the local Hillside Cemetery on 17 June 1882.