A373006 Antidiagonal sums of A373005.

1, 2, 6, 10, 20, 41, 84, 162, 324, 637, 1276, 2509, 5018, 9907, 19816, 39202, 78404, 155381, 310764, 616665, 1233330, 2449867, 4899736, 9740685, 19481370, 38754731, 77509464, 154276027, 308552054, 614429671, 1228859344, 2448023842, 4896047684, 9756737701, 19513475404

Offset: 0

Author

Stefano Spezia, May 19 2024

Keywords

• nonn

Crossrefs

Cf. A000079, A373005.

Programs

Mathematica

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]

Formula

Limit_{n->oo} a(n)/a(n-1) = 2.