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%I #15 Jan 14 2016 10:56:44
%S 1,7,39,206,1087,5832,31949,178486,1013667,5832452,33896809,198496866,
%T 1168995647,6913808272,41021119269,243974552846,1453712656027,
%U 8674107635292,51813825111329,309768931954426,1853203840458807,11092815661905512,66427422581744989,397927440625389606,2384420217810707987
%N Expansion of (1-11*x+34*x^2-21*x^3+2*x^4)/((1-x)*(1-2*x)*(1-4*x)*(1-5*x)*(1-6*x)).
%H Colin Barker, <a href="/A246987/b246987.txt">Table of n, a(n) for n = 0..1000</a>
%H A. Prasad, <a href="http://arxiv.org/abs/1407.5284">Equivalence classes of nodes in trees and rational generating functions</a>, arXiv preprint arXiv:1407.5284 [math.CO], 2014
%H <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (18,-121,372,-508,240).
%F a(n) = (1 - 3*2^(2+n) + 7*2^(1+2*n) + 3*5^n + 6^(1+n)) / 12. - _Colin Barker_, Jun 06 2015
%o (PARI) Vec((2*x^4-21*x^3+34*x^2-11*x+1)/(-240*x^5+508*x^4-372*x^3+121*x^2-18*x+1) + O(x^40)) \\ _Colin Barker_, Jun 06 2015
%K nonn,easy
%O 0,2
%A _N. J. A. Sloane_, Sep 15 2014