Gamma
de Julian Havil
Exploring Euler's constant. Swiss mathematician Leonhard Euler (1707-1783) introduced gamma as the limit of the sum of 1 + 1/2 + 1/3 + . . . up to 1/n, minus the natural logarithm of n--the numerical value being 0.5772156. Unlike its more celebrated colleagues p and e, the exact nature of gamma remains a mystery.
