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%I #12 Feb 15 2020 10:52:26
%S 0,32,27000,24193888,21724523760,19508551374752,17518656008529000,
%T 15731733545110199008,14127079203594427607520,
%U 12686101393056537201642272,11392104923884436660778375000
%N Values X satisfying the equation 7(X-Y)^4-2XY=0, where X>=Y.
%C To find Y values: b(n) = c(n)*(-1+d(n)) which gives: 0, 28, 26880, 24190292, 21724416000, ...
%H G. C. Greubel, <a href="/A123393/b123393.txt">Table of n, a(n) for n = 0..335</a>
%F a(n) = c(n)*(1+d(n)) with c(0) = 0, c(1) = 2 and c(n) = 30*c(n-1) - c(n-2), d(0) = 1, d(1) = 15 and d(n) = 30*d(n-1) - d(n-2).
%F From _Max Alekseyev_, Nov 13 2009: (Start)
%F For n>=4, a(n) = 928*a(n-1) - 26942*a(n-2) + 928*a(n-3) - a(n-4).
%F O.g.f.: 8*x*(4*x^2 -337*x +4)/((x^2 -30*x +1)*(x^2 -898*x +1)). (End)
%t CoefficientList[Series[8*x*(4*x^2 - 337*x + 4)/(x^2 - 30*x + 1)/(x^2 - 898*x + 1), {x, 0, 50}], x] (* _G. C. Greubel_, Oct 13 2017 *)
%o (PARI) x='x+O('x^50); concat([0], Vec(8*x*(4*x^2 -337*x +4)/((x^2 -30*x +1)*(x^2 -898*x +1)))) \\ _G. C. Greubel_, Oct 13 2017
%K nonn
%O 0,2
%A _Mohamed Bouhamida_, Oct 14 2006
%E More terms from _Max Alekseyev_, Nov 13 2009
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