<P> In 1789, the Slovene mathematician Jurij Vega calculated the first 140 decimal places for π of which the first 126 were correct and held the world record for 52 years until 1841, when William Rutherford calculated 208 decimal places of which the first 152 were correct . Vega improved John Machin's formula from 1706 and his method is still mentioned today . </P> <P> The magnitude of such precision (152 decimal places) can be put into context by the fact that the circumference of the largest known object, the observable universe, can be calculated from its diameter (93 billion light - years) to a precision of less than one Planck length (at 6965161620000000000 ♠ 1.6162 × 10 meters, the shortest unit of length that has real meaning) using π expressed to just 62 decimal places . </P> <P> The English amateur mathematician William Shanks, a man of independent means, spent over 20 years calculating π to 707 decimal places . This was accomplished in 1873, with the first 527 places correct . He would calculate new digits all morning and would then spend all afternoon checking his morning's work . This was the longest expansion of π until the advent of the electronic digital computer three - quarters of a century later . </P> <P> In 1910, the Indian mathematician Srinivasa Ramanujan found several rapidly converging infinite series of π, including </P>

What english mathematician calculated the value of pi to 707