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 A131442 #17 Jan 28 2025 08:35:59
%S A131442 1,91,10038,1467290,281838271,69542401565,21540814788284,
%T A131442 8205391883388996,3775954944255499341,2067250635545212529775,
%U A131442 1328812758711335378653074,991440081612864413673579774,850081840027433295638565899691,830293567537520120294141671187025
%N A131442 Sixth column (m=5) of triangle A060524 without zeros.
%C A131442 a(n) = sum over all M2(2*n+5,k), k from {1..p(2*n+5)} restricted to partitions with exactly five odd and possibly even parts. p(2*n+5) = A000041(2*n+5) (partition numbers) and for the M2-multinomial numbers in A-St order see A036039(2*n+5,k).
%F A131442 E.g.f. (with alternating zeros): A(x) = (d^5/dx^5) a(x) with a(x):=(1/(sqrt(1-x^2))*(log(sqrt((1+x)/(1-x))))^5)/5! = (1/(sqrt(1-x^2)))*(arctanh(x)^5)/5!.
%F A131442 a(n) = A060524(2*n+5,5), n >= 0.
%e A131442 Multinomial representation for a(2): partitions of 2*2+5=9 with five odd parts: (1^4,5) with A-St position k=19; (1^3,3^2) with k=21; (1^5,4) with k=24; (1^4,2,3) with k=25 and (1^5,2^2) with k=28. The M2 numbers for these partitions are 3024, 3360, 756, 2520, 378, adding up to 10038 = a(2).
%Y A131442 Cf. A000041, A036039, A060524.
%K A131442 nonn,easy
%O A131442 0,2
%A A131442 _Wolfdieter Lang_, Aug 07 2007