OFFSET
4,2
COMMENTS
Is this the same as A026841? - R. J. Mathar, Oct 23 2008
Column k=10 of triangle A236830. - Philippe Deléham, Feb 02 2014
LINKS
G. C. Greubel, Table of n, a(n) for n = 4..1000
FORMULA
a(n) = A026841(n). - Philippe Deléham, Feb 02 2014
G.f.: (x^4*C(x)^10)/(1-x*C(x)^3) where C(x) is the g.f. of A000108. - Philippe Deléham, Feb 02 2014
MATHEMATICA
Drop[CoefficientList[Series[(1-Sqrt[1-4*x])^10/(128*x^4*(8*x^2 -(1 - Sqrt[1-4*x])^3 )), {x, 0, 40}], x], 4] (* G. C. Greubel, Jul 17 2019 *)
PROG
(PARI) my(x='x+O('x^40)); Vec((1-sqrt(1-4*x))^10/(128*x^4*(8*x^2 -(1 - sqrt(1-4*x))^3 ))) \\ G. C. Greubel, Jul 17 2019
(Magma) R<x>:=PowerSeriesRing(Rationals(), 40); Coefficients(R!( (1-Sqrt(1-4*x))^10/(128*x^4*(8*x^2 -(1-Sqrt(1-4*x))^3 )) )); // G. C. Greubel, Jul 17 2019
(Sage) a=((1-sqrt(1-4*x))^10/(128*x^4*(8*x^2 -(1-sqrt(1-4*x))^3 ))).series(x, 45).coefficients(x, sparse=False); a[4:40] # G. C. Greubel, Jul 17 2019
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved