A183203 Antidiagonal sums of triangle A183202.

1, 1, 3, 4, 9, 14, 31, 53, 117, 215, 478, 930, 2092, 4266, 9732, 20645, 47820, 104941, 246931, 558190, 1334462, 3097018, 7521731, 17874931, 44092014

Offset

0,3

Links

Table of n, a(n) for n=0..24.

Prog

(PARI) {A131338(n, k)=if(k>n*(n+1)/2|k<0, 0, if(k<=n, 1, sum(i=0, k-n, A131338(n-1, i))))}
{A183202(n, k)=if(n==k, A131338(n, n*(n+1)/2), sum(j=n*k-k*(k-1)/2, n*k-k*(k-1)/2+n-k-1, A131338(n, j)))}
{a(n)=sum(k=0, n, A183202(n-k, k))}

Crossrefs

Cf. A183202.

Sequence in context: A096081 A054162 A174783 * A321680 A215667 A125874

Adjacent sequences: A183200 A183201 A183202 * A183204 A183205 A183206

Keyword

more,nonn

Author

Paul D. Hanna, Dec 30 2010

Status

approved