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A123890
Expansion of g.f.: x/((1-x^2)^5 - 1 + x).
1
1, 5, 25, 115, 525, 2385, 10825, 49120, 222875, 1011251, 4588335, 20818575, 94459755, 428590575, 1944636420, 8823364350, 40034094615, 181645987625, 824179118751, 3739533301365, 16967318139775, 76985511735170, 349304997307275, 1584895370489480
OFFSET
0,2
LINKS
A. Burstein and T. Mansour, Words restricted by 3-letter ..., arXiv:math/0112281 [math.CO], 2001.
A. Burstein and T. Mansour, Words Restricted by 3-Letter Generalized Multipermutation Patterns, Annals. Combin., 7 (2003), 1-14.
MAPLE
seq(coeff(series(1/(1-5*x+10*x^3-10*x^5+5*x^7-x^9), x, n+1), x, n), n = 0 .. 30); # G. C. Greubel, Aug 07 2019
MATHEMATICA
CoefficientList[Series[x/((1-x^2)^5 -1+x), {x, 0, 30}], x] (* G. C. Greubel, Aug 07 2019 *)
PROG
(PARI) my(x='x+O('x^30)); Vec(x/((1-x^2)^5 -1+x)) \\ G. C. Greubel, Aug 07 2019
(Magma) R<x>:=PowerSeriesRing(Integers(), 30); Coefficients(R!( x/((1-x^2)^5 -1+x) )); // G. C. Greubel, Aug 07 2019
(Sage)
def A123890_list(prec):
P.<x> = PowerSeriesRing(ZZ, prec)
return P( x/((1-x^2)^5 -1+x) ).list()
A123890_list(30) # G. C. Greubel, Aug 07 2019
(GAP) a:=[1, 5, 25, 115, 525, 2385, 10825, 49120, 222875];; for n in [10..30] do a[n]:=5*a[n-1]-10*a[n-3] +10*a[n-5]-5*a[n-7]+a[n-9]; od; a; # G. C. Greubel, Aug 07 2019
CROSSREFS
Sequence in context: A261383 A089947 A267467 * A123894 A200781 A055297
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, Nov 20 2006
STATUS
approved