Landau–Ramanujan constant
In mathematics and the field of number theory, the Landau–Ramanujan constant is the positive real number b that occurs in a theorem proved by Edmund Landau in 1908, stating that for large x {\displaystyle x} , the number of positive integers below x {\displaystyle x} that are the sum of two square numbers behaves asymptotically as b x log ( x ) . {\displaystyle {\dfrac {bx}{\sqrt {\log(x)}}}.} This constant b was rediscovered in 1913 by Srinivasa Ramanujan, in the first letter he wrote to G.H. Hardy.
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