A143961 - OEIS

A143961

Binomial transform of A010054 (characteristic function of triangular numbers).

1, 2, 3, 5, 9, 16, 28, 50, 93, 178, 342, 650, 1223, 2302, 4383, 8480, 16609, 32658, 63973, 124375, 240181, 462597, 893388, 1737375, 3407429, 6729596, 13336532, 26415118, 52129356, 102359648, 200067986, 389989828, 760206585, 1485887074, 2917775247, 5759836217

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OFFSET

0,2

LINKS

Alois P. Heinz, Table of n, a(n) for n = 0..1000

N. J. A. Sloane, Transforms

FORMULA

a(n) = Sum_{k=0..n} C(n,k) * A010054(k).

EXAMPLE

a(4) = [1,4,6,4,1]*[1,1,0,1,0] = 1+4+4 = 9.

MAPLE

a:= proc(n) local k, i, s; k:=0; i:=0; s:=0; while k<=n do s:= s+binomial(n, k); i:=i+1; k:=k+i; od; s end: seq(a(n), n=0..40);