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%I #8 May 06 2022 15:12:44
%S 6,7,2,4,6,2,9,6,6,9,3,6,3,6,3,6,2,4,9,2,8,3,3,6,1,9,7,8,6,2,3,0,3,1,
%T 8,4,8,1,6,8,2,4,7,3,0,5,5,3,0,1,7,1,3,8,9,7,3,8,1,2,1,3,3,7,5,2,1,0,
%U 2,8,6,5,3,6,3,9,1,4,0,5,9,6,9,8,8,2,4,7,1,4,3,2,6,7,6,4,2,7,1,3,9,1,3,7,3,1,3,2,0,5
%N Decimal expansion of Pi * BesselY(0,2) / 2 - gamma * BesselJ(0,2).
%F Equals Sum_{k>=1} (-1)^(k+1) * H(k) / (k!)^2, where H(k) is the k-th harmonic number.
%e 0.672462966936363624928336197862303184816824730553017...
%t RealDigits[Pi BesselY[0, 2]/2 - EulerGamma BesselJ[0, 2], 10, 110] [[1]]
%o (PARI) Pi*bessely(0,2)/2 - Euler*besselj(0,2) \\ _Michel Marcus_, Apr 20 2022
%Y Cf. A000796, A001008, A001044, A001620, A002805, A091681, A233090, A347952, A348573, A351164.
%K nonn,cons
%O 0,1
%A _Ilya Gutkovskiy_, Apr 20 2022