A372838 - OEIS

A372838

Decimal expansion of Sum_{k>=1} (1 - cos(Pi/k^2)).

2, 3, 9, 0, 0, 2, 5, 0, 7, 8, 1, 6, 2, 3, 3, 4, 4, 3, 6, 1, 8, 6, 0, 1, 7, 2, 6, 5, 7, 8, 4, 5, 0, 2, 4, 8, 3, 5, 0, 0, 4, 0, 2, 2, 1, 2, 6, 0, 4, 3, 6, 1, 4, 3, 6, 3, 5, 6, 5, 6, 5, 6, 0, 4, 0, 5, 6, 8, 9, 9, 4, 8, 0, 5, 3, 6, 0, 0, 8, 9, 0, 1, 1, 3, 8, 6

(list; constant; graph; refs; listen; history; text; internal format)

OFFSET

1,1

LINKS

Table of n, a(n) for n=1..86.

EXAMPLE

2.39002507816233443618601726578450248350040221260...

MATHEMATICA

s = Sum[(1 - Cos[Pi/k^2]), {k, 1, Infinity}]

d = N[s, 100]

First[RealDigits[d]]

CROSSREFS