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 A359060 #10 Jun 21 2023 06:37:46
%S A359060 4,2,3,0,1,0,4,7,5,0,3,7,3,3,5,0,8,0,6,6,8,6,4,2,8,4,0,6,2,5,3,0,7,6,
%T A359060 4,5,3,0,5,9,5,6,7,0,6,2,2,4,9,3,3,2,3,1,5,5,1,1,8,8,7,6,9,4,9,4,2,6,
%U A359060 8,9,9,1,3,1,9,7,6,5,8,1,2
%N A359060 Decimal expansion of Sum_{n >= 1} sigma_4(n)/n!.
%C A359060 This constant's irrationality was conjectured by Erdős and Kac in 1953 and proved by Pratt in 2022.
%H A359060 Paul Erdős and Mark Kac, <a href="http://www.jstor.org/stable/2306485">Problem 4518</a>, American Mathematical Monthly, Vol. 60, No. 1 (1953), p. 47.
%H A359060 Kyle Pratt, <a href="https://arxiv.org/abs/2209.11124">The irrationality of a divisor function series of Erdős and Kac</a>, arXiv preprint, arXiv:2209.11124 [math.NT], 2022.
%e A359060 42.301047503733508066864284062530764530595670622493323155118876949426899131....
%t A359060 RealDigits[N[Sum[DivisorSigma[4, n]/n!, {n, 1, 500}], 120]][[1]] (* _Amiram Eldar_, Jun 21 2023 *)
%o A359060 (PARI) suminf(n=1,sigma(n,4)/n!)
%Y A359060 Sum_{n >= 1} sigma_k(n)/n!: A227988 (k=1), A227989 (k=2), A307036 (k=3), this sequence (k=4).
%K A359060 cons,nonn
%O A359060 2,1
%A A359060 _Charles R Greathouse IV_, Dec 14 2022