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Expansion of 1/((1-x)*(1-x^5)*(1-x^7)).
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%I #12 Feb 28 2020 04:07:28

%S 1,1,1,1,1,2,2,3,3,3,4,4,5,5,6,7,7,8,8,9,10,11,12,12,13,14,15,16,17,

%T 18,19,20,21,22,23,25,26,27,28,29,31,32,34,35,36,38,39,41,42,44,46,47,

%U 49,50,52,54,56,58,59,61,63,65,67,69,71,73,75,77,79,81,84

%N Expansion of 1/((1-x)*(1-x^5)*(1-x^7)).

%D L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 120, D(n;1,5,7).

%H <a href="/index/Rec#order_13">Index entries for linear recurrences with constant coefficients</a>, signature (1,0,0,0,1,-1,1,-1,0,0,0,-1,1).

%F a(n) = round((n^2+13*n+36)/70).

%F a(n) = a(n-1) + a(n-5) - a(n-6) + a(n-7) - a(n-8) - a(n-12) + a(n-13). - _R. J. Mathar_, Aug 21 2014

%t CoefficientList[Series[1/((1-x)(1-x^5)(1-x^7)),{x,0,60}],x] (* or *) LinearRecurrence[{1,0,0,0,1,-1,1,-1,0,0,0,-1,1},{1,1,1,1,1,2,2,3,3,3,4,4,5},70] (* _Harvey P. Dale_, Apr 30 2018 *)

%o (PARI) Vec(1/((1-x)*(1-x^5)*(1-x^7)) + O(x^70)) \\ _Jinyuan Wang_, Feb 28 2020

%K nonn,easy

%O 0,6

%A _N. J. A. Sloane_

%E More terms from _Jinyuan Wang_, Feb 28 2020