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%I #15 Jul 30 2016 19:55:56
%S 0,-7,-20,-27,-16,25,108,245,448,729,1100,1573,2160,2873,3724,4725,
%T 5888,7225,8748,10469,12400,14553,16940,19573,22464,25625,29068,32805,
%U 36848,41209,45900,50933,56320,62073
%N a(n) = (2*n - 9)*n^2.
%H Ivan Panchenko, <a href="/A015243/b015243.txt">Table of n, a(n) for n = 0..1000</a>
%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (4,-6,4,-1).
%F G.f.: x*(-7 + 8*x + 11*x^2)/(1-x)^4. - _Ivan Panchenko_, Nov 09 2013
%F From _G. C. Greubel_, Jul 30 2016: (Start)
%F a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4).
%F E.g.f.: x*(-7 - 3*x + 2*x^2)*exp(x). (End)
%t Table[(2*n - 9)*n^2, {n,0,25}] (* or *) LinearRecurrence[{4,-6,4,-1},{0, -7, -20, -27},25] (* _G. C. Greubel_, Jul 30 2016 *)
%o (PARI) a(n)=(2*n-9)*n^2 \\ _Charles R Greathouse IV_, Jul 30 2016
%K sign,easy
%O 0,2
%A _N. J. A. Sloane_, Dec 11 1999
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