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 A371804 #8 Apr 26 2024 07:57:48
%S A371804 7,6,1,3,1,0,2,0,4,0,0,1,1,0,3,4,8,6,3,8,8,7,3,1,2,7,8,6,7,7,8,3,8,4,
%T A371804 1,1,6,0,4,8,8,2,7,1,5,7,7,9,7,2,6,0,9,5,2,2,6,8,2,1,7,0,3,3,3,3,9,4,
%U A371804 4,7,5,6,1,0,6,0,3,8,2,8,3,6,4,4,1,8
%N A371804 Decimal expansion of Sum_{k>=0} (-1)^k / (k^2 + k + 1).
%e A371804 0.761310204001103486388731278677838411604882...
%t A371804 s = Chop[N[Sum[(-1)^k/(k^2 + k + 1), {k, 0, Infinity}], 120]]
%t A371804 First[RealDigits[s]]
%Y A371804 Cf. A372253.
%K A371804 nonn,cons
%O A371804 0,1
%A A371804 _Clark Kimberling_, Apr 24 2024