A145423 - OEIS

%I #9 Jun 27 2017 06:22:59

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

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

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

%N Decimal expansion of Sum_{n>=1} (-1)^(n-1)/(n^2-1/4)^2.

%D Alexander Apelblat, Tables of Integrals and Series, Harri Deutsch, (1996), 4.1.18

%H G. C. Greubel, <a href="/A145423/b145423.txt">Table of n, a(n) for n = 1..5000</a>

%F Equals 8 - A019692 = 8 - 2*Pi.

%e 1.7168146928204135...

%p evalf(8-2*Pi) ;

%t RealDigits[8 - 2*Pi, 10, 50][[1]] (* _G. C. Greubel_, Jun 26 2017 *)

%o (PARI) 8 - 2*Pi \\ _G. C. Greubel_, Jun 26 2017

%K cons,easy,nonn

%O 1,2

%A _R. J. Mathar_, Feb 08 2009