A067301 One eighth of fourth column of triangle A067298.

8, 41, 398, 4460, 53720, 677744, 8836832, 118109888, 1609484672, 22276767488, 312305704448, 4425515174912, 63285369657344, 912105965121536, 13235652537933824, 193215065765888000, 2835518953336438784

Offset: 0

Author

Wolfdieter Lang, Feb 05 2002

Keywords

• nonn
• easy

Crossrefs

Cf. A000108, A067298.

Cf. 3*A067300 (third column).

Formula

a(n) = A067298(n+3, 3)/8.

G.f.: ((-3+37*x)+(3+15*x-84*x^2)*c(4*x))/(8*x*(1-2*x*c(4*x))^2), with c(x) is g.f. for A000108 (Catalan).