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%I #24 Jul 03 2023 08:18:44
%S 1,11,100,368,1696,6656,27520,109568,441856,1765376,7075840,28295168,
%T 113238016,452919296,1811906560,7247495168,28990898176,115963068416,
%U 463855943680,1855421677568,7421701390336,29686797172736
%N Expansion of (1-x)*(1+8*x+60*x^2)/((1-2*x)*(1+2*x)*(1-4*x)).
%H G. C. Greubel, <a href="/A120655/b120655.txt">Table of n, a(n) for n = 0..1000</a>
%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (4, 4, -16).
%F From _Colin Barker_, Oct 19 2012: (Start)
%F a(n) = 3*(-2)^n - 5*2^n + 27*4^(n-1) for n>0.
%F a(n) = 4*a(n-1) + 4*a(n-2) - 16*a(n-3) for n>3.
%F G.f.: (1-x)*(1+8*x+60*x^2)/((1-2*x)*(1+2*x)*(1-4*x)). (End)
%t LinearRecurrence[{4,4,-16}, {1,11,100,368}, 50] (* _G. C. Greubel_, Dec 20 2022 *)
%o (Magma) [1] cat [3*(-2)^n - 5*2^n + 27*4^(n-1): n in [1..40]]; // _G. C. Greubel_, Dec 20 2022
%o (SageMath) [3*(-2)^n - 5*2^n + 27*4^(n-1) - (15/4)*int(n==0) for n in range(41)] # _G. C. Greubel_, Dec 20 2022
%Y Cf. A105932, A105933.
%K nonn,easy,less
%O 0,2
%A _Roger L. Bagula_, Aug 09 2006
%E Edited by _G. C. Greubel_, Dec 20 2022
%E Meaningful name using g.f. from _Joerg Arndt_, Dec 26 2022
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