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A159972
Row sums of number triangle A159971.
1
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
0,4
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
CROSSREFS
Sequence in context: A005666 A353094 A291411 * A106271 A027990 A037520
KEYWORD
easy,sign
AUTHOR
Paul Barry, Apr 28 2009
STATUS
approved