login
A147618
The 3rd Witt transform of A000217.
2
0, 0, 0, 0, 3, 15, 54, 165, 429, 999, 2145, 4290, 8100, 14586, 25194, 41985, 67830, 106590, 163431, 245157, 360525, 520749, 740025, 1036035, 1430703, 1950975, 2629575, 3506085, 4628052, 6052068, 7845255, 10086780, 12869340, 16301142
OFFSET
0,5
COMMENTS
The 2nd Witt transform of A000217 is essentially in A032092.
LINKS
Pieter Moree, The formal series Witt transform, Discr. Math. no. 295 vol. 1-3 (2005) 143-160.
Index entries for linear recurrences with constant coefficients, signature (6,-15,23,-33,51,-64,63,-63,64,-51,33,-23,15,-6,1).
FORMULA
G.f.: 3*x^4*(1-x+3*x^2-x^3+x^4)/((1-x)^9*(1+x+x^2)^3).
a(n) = (1/81)*(n*(n+3)*(3*n^6 +27*n^5 +45*n^4 -135*n^3 -288*n^2 +108*n -2000)/4480 +2*A049347(n) +A049347(n-1) +(-1)^n*(A099254(n) -2*A099254(n- 1)) -3*(-1)^n*(A128504(n) -2*A128504(n-1))). - G. C. Greubel, Oct 24 2022
MATHEMATICA
CoefficientList[Series[3*x^4*(1-x+3*x^2-x^3+x^4)/((1-x)^9*(1+x+x^2)^3), {x, 0, 40}], x] (* Vincenzo Librandi, Dec 13 2012 *)
PROG
(Magma) R<x>:=PowerSeriesRing(Integers(), 30); [0, 0, 0, 0] cat Coefficients(R!( 3*x^4*(1-x+3*x^2-x^3+x^4)/((1-x)^9*(1+x+x^2)^3) )); // G. C. Greubel, Oct 24 2022
(SageMath)
def A147618_list(prec):
P.<x> = PowerSeriesRing(ZZ, prec)
return P( 3*x^4*(1-x+3*x^2-x^3+x^4)/((1-x)^9*(1+x+x^2)^3) ).list()
A147618_list(30) # G. C. Greubel, Oct 24 2022
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
R. J. Mathar, Nov 08 2008
STATUS
approved