This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A377557 #13 Jul 14 2025 16:43:22
%S A377557 1,0,2,0,7,8,0,0,4,4,4,3,3,3,6,3,1,0,2,8,2,3,2,5,4,7,3,9,9,0,3,9,8,1,
%T A377557 8,2,5,3,5,3,4,1,0,9,3,7,5,1,9,0,6,9,6,6,9,7,3,5,7,2,0,7,5,2,5,3,9,1,
%U A377557 4,6,5,9,9,2,6,5,6,2,7,1,5,5,4,4,9,8,0,6,7,2,0,3,4,2,6,7,6,1,3,7
%N A377557 Decimal expansion of 2*Pi^3/(81*sqrt(3)) + 13*zeta(3)/27.
%D A377557 Steven R. Finch, Mathematical Constants, Encyclopedia of Mathematics and its Applications, vol. 94, Cambridge University Press, 2003, Section 1.6.3, p. 42.
%H A377557 Michael I. Shamos, <a href="http://euro.ecom.cmu.edu/people/faculty/mshamos/cat.pdf">A catalog of the real numbers</a>, (2007). See p. 52.
%F A377557 Equals Sum_{k>=0} 1/(3*k + 1)^3 (see Finch).
%F A377557 Equals -psi''(1/3)/54 (see Shamos).
%F A377557 Equals hypergeom([1/3, 1/3, 1/3, 1], [4/3, 4/3, 4/3], 1). - _R. J. Mathar_, Jul 14 2025
%e A377557 1.0207800444333631028232547399039818253534109375...
%t A377557 RealDigits[2Pi^3/(81Sqrt[3])+13Zeta[3]/27,10,100][[1]]
%Y A377557 Cf. A002117, A002194, A016777, A016779, A091925, A233091, A377558, A377559, A377560.
%K A377557 nonn,cons
%O A377557 1,3
%A A377557 _Stefano Spezia_, Nov 01 2024