A089976 Antidiagonal sums of array A089975.

1, 1, 2, 4, 8, 20, 52, 146, 458, 1498, 5240, 19562, 76006, 311258, 1334108, 5931250, 27492122, 132096626, 655783888, 3368747018, 17837850110, 97228103482, 545514383396, 3142793126018, 18578114240578, 112620106745570, 698987455899992, 4439420959115866, 28832596784976998, 191284437539842538

Offset

0,3

Links

Table of n, a(n) for n=0..29.

Prog

(PARI) T(n, k) = sum(i=max(0, n-k), floor(n/2), n!*k!/(2^i*(n-2*i)!*(k-n+i)!*i!)); \\ A089975
a(n) = sum(i=0, n, T(i, n-i)); \\ Michel Marcus, Mar 21 2023

Crossrefs

Cf. A089975.

Sequence in context: A078160 A218088 A222320 * A000980 A123611 A082279

Adjacent sequences: A089973 A089974 A089975 * A089977 A089978 A089979

Keyword

easy,nonn

Author

Paul Boddington, Nov 17 2003

Extensions

Name edited and more terms from Michel Marcus, Mar 21 2023

Status

approved