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 A366150 #11 Jan 02 2024 02:43:01 %S A366150 1,1,8,190,9080,725320,87067520,14652451360,3291452374400, %T A366150 951504315644800,344097665398707200,152191547632887731200, %U A366150 80821740082953347993600,50749489515964112842240000,37193794460546391363092480000,31464706192542487393274091520000 %N A366150 a(n) = A366149(n, n). %C A366150 This a weighted generalized Catalan sequence (A365673) with the heptagonal numbers as weights. %p A366150 # Using function T from A366149. %p A366150 a := n -> T(n, n): seq(a(n), n = 0..16); %t A366150 A366149[n_,k_]:=A366149[n,k]=Which[k==0,1,k==n,A366149[n,k-1],True,PolygonalNumber[7,n-k+1]A366149[n,k-1]+A366149[n-1,k]]; %t A366150 Array[A366149[#,#]&,20,0] (* _Paolo Xausa_, Jan 01 2024 *) %Y A366150 Cf. A366149, A365673. %K A366150 nonn %O A366150 0,3 %A A366150 _Peter Luschny_, Oct 01 2023