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a(n) = (-1)^(n+1) * n*(n-1)*(n-4)*(n+1)/12.
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%I #25 Sep 08 2022 08:45:48

%S 1,-2,0,10,-35,84,-168,300,-495,770,-1144,1638,-2275,3080,-4080,5304,

%T -6783,8550,-10640,13090,-15939,19228,-23000,27300,-32175,37674,

%U -43848,50750,-58435,66960,-76384,86768,-98175,110670,-124320,139194,-155363,172900

%N a(n) = (-1)^(n+1) * n*(n-1)*(n-4)*(n+1)/12.

%C The coefficient of [x^4] of the Polynomial B_{2n}(x) defined in A137276.

%C Essentially the same as A052472.

%H G. C. Greubel, <a href="/A167387/b167387.txt">Table of n, a(n) for n = 2..1000</a>

%H <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (-5,-10,-10,-5,-1).

%F a(n) = -5*a(n-1) -10*a(n-2) -10*a(n-3) -5*a(n-4) -a(n-5).

%F G.f.: x^2*(1+3*x)/(1+x)^5.

%F E.g.f.: x^2*(6 + 2*x - x^2)*exp(-x)/12. - _G. C. Greubel_, May 19 2019

%t Table[(-1)^(n+1)*(n+1)*n*(n-1)*(n-4)/12, {n, 2, 40}] (* _G. C. Greubel_, Jun 12 2016 *)

%t LinearRecurrence[{-5, -10, -10, -5, -1}, {1, -2, 0, 10, -35}, 40] (* _Vincenzo Librandi_, Jun 13 2016 *)

%o (Magma) [(-1)^(n+1)*n*(n-1)*(n-4)*(n+1)/12: n in [2..40]]; // _Vincenzo Librandi_, Jun 13 2016

%o (PARI) vector(40, n, n++; (-1)^(n+1)*(n-4)*binomial(n+1,3)/2) \\ _G. C. Greubel_, May 19 2019

%o (Sage) [(-1)^(n+1)*(n-4)*binomial(n+1,3)/2 for n in (2..40)] # _G. C. Greubel_, May 19 2019

%o (GAP) List([2..40], n-> (-1)^(n+1)*(n-4)*Binomial(n+1,3)/2) # _G. C. Greubel_, May 19 2019

%Y Cf. A052472, A137276, A135929, A138034.

%K sign,easy

%O 2,2

%A _Jamel Ghanouchi_, Nov 02 2009