A158840 Row sums of triangle A158835.

1, 2, 7, 42, 374, 4391, 63637, 1095362, 21823226, 493898216, 12515588806, 351062669154, 10798972965266, 361471373319171, 13080119556342713, 508813238759275712, 21174032937728251318, 938646693399848483498

Offset

0,2

Comments

Triangle A158835 transforms diagonals in the array A158825 of coefficients of successive iterations of x*C(x) where C(x) is the Catalan function (A000108).

Links

Table of n, a(n) for n=0..17.

Prog

(PARI) {a(n)=local(F=x, CAT=serreverse(x-x^2+x*O(x^(n+2))), M, N, P); M=matrix(n+2, n+2, r, c, F=x; for(i=1, r+c-2, F=subst(F, x, CAT)); polcoeff(F, c)); N=matrix(n+1, n+1, r, c, M[r, c]); P=matrix(n+1, n+1, r, c, M[r+1, c]); sum(k=0, n, (P~*N~^-1)[n+1, k+1])}

Crossrefs

Cf. A158835, A158836, A158837, A158838, A158839.

Sequence in context: A353257 A368449 A317349 * A359717 A038052 A371079

Adjacent sequences: A158837 A158838 A158839 * A158841 A158842 A158843

Keyword

nonn

Author

Paul D. Hanna, Mar 28 2009

Status

approved