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 A373006 #7 May 27 2024 15:48:00
%S A373006 1,2,6,10,20,41,84,162,324,637,1276,2509,5018,9907,19816,39202,78404,
%T A373006 155381,310764,616665,1233330,2449867,4899736,9740685,19481370,
%U A373006 38754731,77509464,154276027,308552054,614429671,1228859344,2448023842,4896047684,9756737701,19513475404
%N A373006 Antidiagonal sums of A373005.
%F A373006 Limit_{n->oo} a(n)/a(n-1) = 2.
%t A373006 A373005[n_,k_]:=If[OddQ[k],Sum[Binomial[n,i],{i,0,(k-1)/2}],Sum[Binomial[n,i],{i,0,k/2-1}]+Binomial[n-1,k/2-1]]; a[n_]:=Sum[A373005[n-k,n],{k,0,n}]; Array[a,35,0]
%Y A373006 Cf. A000079, A373005.
%K A373006 nonn
%O A373006 0,2
%A A373006 _Stefano Spezia_, May 19 2024