A067324 - OEIS

A067324

Third column of triangle A067323.

2, 7, 23, 76, 255, 869, 3003, 10504, 37128, 132430, 476102, 1723528, 6277505, 22988385, 84592275, 312636240, 1159979700, 4319218530, 16134883410, 60452176200, 227110782990, 855361970034, 3228982640478

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OFFSET

0,1

COMMENTS

Also third diagonal of triangle A028364.

LINKS

Table of n, a(n) for n=0..22.

FORMULA

a(n)= A067323(n+2, 2)= C(n+3)-(C(n+2)+C(n+1)), C(n) := A000108(n) (Catalan).

G.f.: (c(x)^3)*(1+c(x)), with c(x) g.f. of A000108 (Catalan).

CROSSREFS

Cf. A000245 (second column).

Sequence in context: A042575 A256030 A052924 * A047062 A292231 A292232

Adjacent sequences: A067321 A067322 A067323 * A067325 A067326 A067327

KEYWORD

nonn,easy

AUTHOR

Wolfdieter Lang, Feb 05 2002

STATUS

approved