A027131 a(n) = diagonal sum of left justified array T given by A027113.

1, 1, 2, 4, 4, 8, 11, 15, 24, 35, 48, 75, 108, 152, 232, 336, 477, 721, 1046, 1496, 2245, 3264, 4690, 7006, 10200, 14709, 21897, 31916, 46148, 68523, 99962, 144841, 214634, 313327, 454756, 672803, 982718, 1428225, 2110278, 3083747, 4486717, 6622251, 9680743, 14098072, 20789712

Offset

0,3

Links

Table of n, a(n) for n=0..44.

Formula

a(n) = Sum_{k=0..n} A027113(n-k, k). - Sean A. Irvine, Oct 23 2019

Crossrefs

Sequence in context: A034408 A227333 A223317 * A338986 A319803 A055946

Adjacent sequences: A027128 A027129 A027130 * A027132 A027133 A027134

Keyword

nonn

Author

Clark Kimberling

Extensions

More terms from Sean A. Irvine, Oct 23 2019

Status

approved