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

0,2

Links

Table of n, a(n) for n=0..34.

Formula

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

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]

Crossrefs

Cf. A000079, A373005.

Sequence in context: A198381 A309846 A309874 * A317759 A014279 A050543

Adjacent sequences: A373003 A373004 A373005 * A373007 A373008 A373009

Keyword

nonn

Author

Stefano Spezia, May 19 2024

Status

approved