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 A085389 #22 Aug 07 2025 15:25:54 %S A085389 1,2,12,100,1080,14406,229376,4251528,90000000,2143588810,56757583872, %T A085389 1654301902188,52644347205632,1816448730468750,67553994410557440, %U A085389 2694045224950414864,114692890480116793344,5191945444217181018258,249036800000000000000000,12617615847934310595791220 %N A085389 a(1) = 1; for n >= 2, a(n) = (n*(n+1)^(n-1))/(n+1). %H A085389 Paolo Xausa, <a href="/A085389/b085389.txt">Table of n, a(n) for n = 1..350</a> %H A085389 Milan Janjic, <a href="https://old.pmf.unibl.org/wp-content/uploads/2017/10/enumfun.pdf">Enumerative Formulas for Some Functions on Finite Sets</a> %F A085389 Main subdiagonal of A085388. %F A085389 a(n) = A055865(n), n>1. - _R. J. Mathar_, Sep 12 2008 %F A085389 a(n) = [x^n] x*(1 - x)/(1 - x - n*x). - _Ilya Gutkovskiy_, Oct 02 2017 %t A085389 A085389[n_] := If[n == 1, 1, n*(n+1)^(n-2)]; %t A085389 Array[A085389, 25] (* _Paolo Xausa_, Aug 07 2025 *) %Y A085389 Cf. A053506, A085390. %K A085389 easy,nonn %O A085389 1,2 %A A085389 _Paul Barry_, Jun 30 2003 %E A085389 Name edited by _Paolo Xausa_, Aug 07 2025