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%I #23 Sep 08 2022 08:44:36
%S 1,0,0,1,1,1,2,1,2,3,3,3,5,4,5,7,7,7,10,9,11,13,13,14,18,17,19,22,23,
%T 24,29,28,31,35,36,38,44,43,47,52,54,56,63,63,68,74,76,79,88,88,94,
%U 101,104,108,118,119,126,134,138,143,155,156,164,174,179,185,198,200,210,221,227
%N Expansion of 1/((1-x^3)*(1-x^4)*(1-x^5)*(1-x^6)).
%H Vincenzo Librandi, <a href="/A008681/b008681.txt">Table of n, a(n) for n = 0..1000</a>
%H INRIA Algorithms Project, <a href="http://ecs.inria.fr/services/structure?nbr=237">Encyclopedia of Combinatorial Structures 237</a>
%H <a href="/index/Rec#order_18">Index entries for linear recurrences with constant coefficients</a>, signature (0,0,1,1,1,1,-1,-1,-2,-1,-1,1,1,1,1,0,0,-1).
%p seq(coeff(series(1/mul(1-x^j, j=3..6), x, n+1), x, n), n = 0..80); # _G. C. Greubel_, Sep 09 2019
%t CoefficientList[Series[1/((1-x^3)(1-x^4)(1-x^5)(1-x^6)), {x,0,80}], x] (* _Vincenzo Librandi_, Jun 23 2013 *)
%o (PARI) my(x='x+O('x^80)); Vec(1/prod(j=3,6, 1-x^j)) \\ _G. C. Greubel_, Sep 09 2019
%o (Magma) R<x>:=PowerSeriesRing(Integers(), 80); Coefficients(R!( 1/&*[1-x^j: j in [3..6]] )); // _G. C. Greubel_, Sep 09 2019
%o (Sage)
%o def A008681_list(prec):
%o P.<x> = PowerSeriesRing(ZZ, prec)
%o return P(1/prod(1-x^j for j in (3..6))).list()
%o A008681_list(80) # _G. C. Greubel_, Sep 09 2019
%K nonn,easy
%O 0,7
%A _N. J. A. Sloane_
%E Typo in name fixed by _Vincenzo Librandi_, Jun 23 2013
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