|
%I #15 Dec 30 2023 16:36:48
%S 1,0,1,0,3,0,4,0,7,0,9,0,14,0,17,0,24,0,29,1,38,1,45,3,57,4,66,7,81,9,
%T 93,14,111,17,126,24,148,29,166,38,192,45,214,57,244,66,270,81,305,93,
%U 335,111,375,126,410,148,455
%N Expansion of (1+x^19)/((1-x^2)*(1-x^4)^2*(1-x^6)).
%H G. C. Greubel, <a href="/A027636/b027636.txt">Table of n, a(n) for n = 0..1000</a>
%H B. Runge, <a href="http://projecteuclid.org/euclid.nmj/1118775400">On Siegel modular forms II</a>, Nagoya Math. J., 138 (1995), 179-197.
%H <a href="/index/Rec#order_15">Index entries for linear recurrences with constant coefficients</a>, signature (1,0,0,2,-2,1,-1,-1,1,-2,2,0,0,1,-1).
%F G.f.: (1+x^19)/((1-x^2) * (1-x^4)^2 * (1-x^6)).
%t CoefficientList[Series[(1+x^19)/((1-x^2)(1-x^4)^2(1-x^6)),{x,0,70}],x] (* _Harvey P. Dale_, Oct 13 2015 *)
%o (Magma) R<x>:=PowerSeriesRing(Integers(), 70); Coefficients(R!( (1+x^19)/((1-x^2)*(1-x^4)^2*(1-x^6) )); // _G. C. Greubel_, Aug 04 2022
%o (Sage)
%o def A027636_list(prec):
%o P.<x> = PowerSeriesRing(ZZ, prec)
%o return P( (1+x^19)/((1-x^2)*(1-x^4)^2*(1-x^6) ).list()
%o A027636_list(70) # _G. C. Greubel_, Aug 04 2022
%Y Cf. A027640.
%K nonn
%O 0,5
%A _N. J. A. Sloane_
|
