A159972 Row sums of number triangle A159971.

1, -1, 0, 2, -7, 21, -63, 195, -624, 2054, -6916, 23712, -82498, 290510, -1033410, 3707850, -13402695, 48760365, -178405155, 656043855, -2423307045, 8987427465, -33453694485, 124936258125, -467995871775, 1757900019099, -6619846420551

Offset: 0

Author

Paul Barry, Apr 28 2009

Keywords

• easy
• sign

Formula

G.f.: (2c(-x)-1)/(1-xc(-x)^3)=(1-x+xc(-x))/(1+x)=(1-2x+sqrt(1+4x))/(2(1+x)), c(x) the g.f. of A000108.

Apparently n*a(n) +(5*n-6)*a(n-1) +2*(2*n-3)*a(n-2)=0. - R. J. Mathar, Oct 25 2012