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%I A011925 #28 Sep 08 2022 08:44:37
%S A011925 0,0,0,0,1,8,24,56,112,201,336,528,792,1144,1601,2184,2912,3808,4896,
%T A011925 6201,7752,9576,11704,14168,17001,20240,23920,28080,32760,38001,43848,
%U A011925 50344,57536,65472,74201,83776
%N A011925 a(n) = floor(n*(n-1)*(n-2)*(n-3)/15).
%H A011925 Vincenzo Librandi, <a href="/A011925/b011925.txt">Table of n, a(n) for n = 0..1000</a>
%H A011925 <a href="/index/Rec#order_09">Index entries for linear recurrences with constant coefficients</a>, signature (4,-6,4,-1,1,-4,6,-4,1).
%F A011925 From _R. J. Mathar_, Apr 15 2010: (Start)
%F A011925 a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4) + a(n-5) - 4*a(n-6) + 6*a(n-7) - 4*a(n-8) + a(n-9).
%F A011925 G.f.: x^4*(x^4 + 4*x^3 - 2*x^2 + 4*x + 1) / ( (1-x)^5*(x^4 + x^3 + x^2 + x + 1) ). (End)
%p A011925 A011925:=n->floor(n*(n-1)*(n-2)*(n-3)/15); seq(A011925(n), n=0..50); # _Wesley Ivan Hurt_, Jan 31 2014
%t A011925 CoefficientList[Series[x^4*(x^4+4*x^3-2*x^2+4*x+1)/((1-x)^5*(x^4+x^3+x^2+x+1)),{x,0,50}],x] (* _Vincenzo Librandi_, Jun 19 2012 *)
%o A011925 (Magma) [Floor(n*(n-1)*(n-2)*(n-3)/15): n in [0..45]]; // _Vincenzo Librandi_, Jun 19 2012
%K A011925 nonn,easy
%O A011925 0,6
%A A011925 _N. J. A. Sloane_

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