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%I #16 Sep 08 2022 08:44:37
%S 0,0,0,0,1,7,22,52,105,189,315,495,742,1072,1501,2047,2730,3570,4590,
%T 5814,7267,8977,10972,13282,15939,18975,22425,26325,30712,35626,41107,
%U 47197,53940,61380,69564,78540
%N a(n) = floor(n*(n-1)*(n-2)*(n-3)/16).
%H <a href="/index/Rec#order_09">Index entries for linear recurrences with constant coefficients</a>, signature (5,-10,10,-6,6,-10,10,-5,1).
%F From _R. J. Mathar_, Apr 15 2010: (Start)
%F G.f.: x^4*(x^4+1+2*x-3*x^2+2*x^3) / ((1-x)^5*(x^4+1) ).
%F a(n) = +5*a(n-1) -10*a(n-2) +10*a(n-3) -6*a(n-4) +6*a(n-5) -10*a(n-6) +10*a(n-7) -5*a(n-8) +a(n-9). (End)
%o (Magma) [Floor(n*(n-1)*(n-2)*(n-3)/16) : n in [0..100]]; // _Wesley Ivan Hurt_, Apr 20 2021
%K nonn,easy
%O 0,6
%A _N. J. A. Sloane_.
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