%I #20 May 03 2024 15:19:39
%S 2,2,3,2,4,4,2,7,5,4,8,3,9,3,2,7,3,0,7,0,5,9,4,1,2,5,0,7,0,3,5,7,4,6,
%T 0,2,9,7,7,4,3,6,5,4,2,2,1,4,6,6,4,3,5,9,0,1,5,6,0,0,6,7,5,3,6,4,9,2,
%U 1,2,0,3,5,5,6,9,5,1,1,0,2,4,1,5,2,3
%N Decimal expansion of Sum_{k>=0} (1)^k * k / ((k+1) (2k)!).
%F Equals 2  cos(1)  2 sin(1).
%e 0.2232442754839327307059412507035746029774...
%t s = Sum[(1)^k k/((k + 1) (2 k)!), {k, 0, Infinity}]
%t d = N[s, 100]
%t First[RealDigits[d]]
%Y Cf. A372339, A372340.
%K nonn,cons
%O 0,1
%A _Clark Kimberling_, May 01 2024
