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 A286193 #16 Jun 12 2025 13:38:48
%S A286193 7,0,4,1,8,8,3,4,9,9,2,3,3,1,4,7,1,8,1,7,1,2,6,2,0,0,0,4,4,2,2,1,8,5,
%T A286193 7,8,0,3,0,4,1,5,8,5,3,7,7,2,9,0,9,4,4,5,0,7,4,2,2,2,3,4,0,3,8,6,1,3,
%U A286193 9,0,6,9,3,8,2,4,0,7,7,6,1,5,5,9,0,4,5,6,8,5,6,2,3,5,3,0,5,6
%N A286193 Decimal expansion of Sum_{n>=1} 1/(n^n+n).
%e A286193 0.70418834992331471817126200044221857803...
%t A286193 RealDigits[N[Sum[1/(n^n+n),{n,1,Infinity}],20]][[1]]
%o A286193 (Python) from decimal import *;getcontext().prec=300;print(sum([Decimal(1)/Decimal(n**n+n)for n in range(1,200)]))
%o A286193 (PARI) suminf(n=1, 1/(n^n+n)) \\ _Michel Marcus_, May 04 2017
%Y A286193 Cf. A073009, A134883.
%K A286193 nonn,cons
%O A286193 0,1
%A A286193 _Jonathan Frech_, May 04 2017