A011905 a(n) = floor( n*(n-1)*(n-2)/23 ).

0, 0, 0, 0, 1, 2, 5, 9, 14, 21, 31, 43, 57, 74, 94, 118, 146, 177, 212, 252, 297, 346, 401, 462, 528, 600, 678, 763, 854, 953, 1059, 1172, 1293, 1423, 1561, 1707, 1862, 2026, 2200, 2384, 2577, 2780, 2994, 3219, 3454, 3701, 3960, 4230, 4512, 4806, 5113, 5432, 5765, 6111, 6470, 6843, 7231, 7633, 8049, 8480, 8926, 9388, 9866, 10359, 10868, 11394, 11937, 12496, 13073

Offset

0,6

Links

G. C. Greubel, Table of n, a(n) for n = 0..2000

Index entries for linear recurrences with constant coefficients, signature (3,-3,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,-3,3,-1).

Formula

G.f.: x^4*(1+x*(-1+x*(2+x*(-1+x^2*(1+(-1+x)*x^2)*(1+x+x^6+x^10+x^13))))) /(1+x*(-3+x*(3+x*(-1+(-1+x)^3*x^20)))). - Peter J. C. Moses, Jun 02 2014

Mathematica

Table[Floor[(n(n-1)(n-2))/23], {n, 0, 75}] (* Harvey P. Dale, Aug 06 2013 *)

Prog

(Magma) [Floor(6*Binomial(n, 3)/23): n in [0..75]]; // G. C. Greubel, Oct 18 2024
(SageMath) [6*binomial(n, 3)//23 for n in range(76)] # G. C. Greubel, Oct 18 2024

Crossrefs

Cf. A011886.

Sequence in context: A363459 A026053 A276031 * A306674 A098065 A123690

Adjacent sequences: A011902 A011903 A011904 * A011906 A011907 A011908

Keyword

nonn,easy

Author

N. J. A. Sloane

Extensions

More terms added by G. C. Greubel, Oct 18 2024

Status

approved