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%I #6 Dec 17 2017 13:04:23
%S 4,4,16,52,188,684,2512,9244,34052,125476,462416,1704212,6280892,
%T 23148428,85314448,314430012,1158845444,4270975556,15740867728,
%U 58013659124,213811888828,788013108844,2904256931152,10703766510172
%N a(n) = 4*a(n-1)-4*a(n-3)-a(n-4).
%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (4,0,-4,-1).
%F G.f.: 4*(1-3*x+x^3)/(1-4*x+4*x^3+x^4) [Sep 28 2009]
%t n = 4; b4 = x /. NSolve[x^4 - n*x^3 + n*x + 1 == 0, x][[4]] b3 = x /. NSolve[x^4 - n*x^3 + n*x + 1 == 0, x][[3]] b2 = x /. NSolve[x^4 - n*x^3 + n*x + 1 == 0, x][[2]] b1 = x /. NSolve[x^4 - n*x^3 + n*x + 1 == 0, x][[1]] digits = 25 a = Table[n*(b4^m + b3^m + b1^m + b2^m)/ (b4 + b3 + b2 + b1), {n, 0, digits}]
%K nonn,easy
%O 0,1
%A _Roger L. Bagula_, May 24 2005
%E Definition replaced by recurrence by the Associate Editors of the OEIS, Sep 28 2009
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