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%I #19 Oct 07 2024 14:06:48
%S 0,0,0,0,3,7,15,26,42,63,90,123,165,214,273,341,420,510,612,726,855,
%T 997,1155,1328,1518,1725,1950,2193,2457,2740,3045,3371,3720,4092,4488,
%U 4908,5355,5827,6327,6854,7410,7995,8610,9255,9933,10642,11385,12161,12972,13818,14700
%N a(n) = floor( n*(n-1)*(n-2)/8 ).
%H G. C. Greubel, <a href="/A011890/b011890.txt">Table of n, a(n) for n = 0..1000</a>
%H <a href="/index/Rec#order_11">Index entries for linear recurrences with constant coefficients</a>, signature (3,-3,1,0,0,0,0,1,-3,3,-1).
%F From _R. J. Mathar_, Apr 15 2010: (Start)
%F a(n) = +3*a(n-1) -3*a(n-2) +a(n-3) +a(n-8) -3*a(n-9) +3*a(n-10) -a(n-11).
%F G.f.: x^4*(3-2*x+3*x^2-x^3+2*x^4+x^6)/((1-x)^4*(1+x)*(1+x^2)*(1+x^4)). (End)
%t Floor[6*Binomial[Range[0,50], 3]/8] (* _G. C. Greubel_, Oct 06 2024 *)
%o (Magma) [Floor(6*Binomial(n,3)/8): n in [0..50]]; // _G. C. Greubel_, Oct 06 2024
%o (SageMath) [6*binomial(n,3)//8 for n in range(51)] # _G. C. Greubel_, Oct 06 2024
%Y Cf. A011886.
%K nonn
%O 0,5
%A _N. J. A. Sloane_
%E a(41) onwards from _G. C. Greubel_, Oct 06 2024