A116870 Seventh column of triangle A028364.

429, 1001, 3003, 9646, 32123, 109550, 380162, 1337220, 4755402, 17065365, 61714147, 224661206, 822574599, 3027096930, 11190101910, 41532876060, 154712622870, 578210935770, 2167431271614, 8146882131276

Offset

0,1

Comments

Also seventh diagonal of triangle A067323.

Links

Table of n, a(n) for n=0..19.

Formula

a(n) = A028364(n+6,6) = Sum_{k=0..6} C(k)*C(n+6-k), with the Catalan numbers C(n):=A000108(n).

G.f.: (c6(x)*c(x)-(c6(x)-1)/x)/x^6, with c6(x) := Sum_{k=0..6} C(k)*x^k and c(x) is the g.f. for the Catalan numbers A000108.

Crossrefs

Cf. A000108, A028364, A067323, A116869 (sixth column).

Sequence in context: A203612 A250330 A034278 * A064061 A244104 A115133

Adjacent sequences: A116867 A116868 A116869 * A116871 A116872 A116873

Keyword

nonn,easy

Author

Wolfdieter Lang, Mar 24 2006

Status

approved