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 A375578 #9 Aug 25 2024 18:49:22
%S A375578 2,3,6,12,24,49,108,274,826,2911,11554,50096,233068,1152293,6019256,
%T A375578 33087782,190780910,1150654755,7241711918,47454746964,323154697536,
%U A375578 2282779992057,16700904490500,126356632392346,987303454931298,7957133905611463,66071772829250362,564631291138147288
%N A375578 Antidiagonal sums of A375577.
%t A375578 A375577[0,0]=2; A375577[n_, k_]:=k^n+k*n+1; a[n_]:=Sum[A375577[n-k,k],{k,0,n}]; Array[a,28,0]
%Y A375578 Cf. A375577.
%K A375578 nonn
%O A375578 0,1
%A A375578 _Stefano Spezia_, Aug 19 2024