A158838 Column 2 of triangle A158835.

1, 3, 21, 217, 2904, 47337, 906557, 19910808, 492818850, 13564326950, 410807572044, 13573135469214, 485765085176420, 18717987193565613, 772565258231236269, 34002334709760133807, 1589555183231724515700

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..16.

Prog

(PARI) {a(n)=local(F=x, CAT=serreverse(x-x^2+x*O(x^(n+4))), M, N, P); M=matrix(n+4, n+4, r, c, F=x; for(i=1, r+c-2, F=subst(F, x, CAT)); polcoeff(F, c)); N=matrix(n+3, n+3, r, c, M[r, c]); P=matrix(n+3, n+3, r, c, M[r+1, c]); (P~*N~^-1)[n+3, 3]}

Crossrefs

Cf. A158835, A158836, A158837, A158839, A158840.

Sequence in context: A372159 A120972 A168479 * A236963 A107716 A032033

Adjacent sequences: A158835 A158836 A158837 * A158839 A158840 A158841

Keyword

nonn

Author

Paul D. Hanna, Mar 28 2009

Status

approved