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A015271
Gaussian binomial coefficient [ n,3 ] for q = -4.
3
1, -51, 3485, -219555, 14107485, -901984419, 57741320029, -3695215419555, 236497451900765, -15135778281070755, 968690748238618461, -61996192875273494691, 3967756584209486471005, -253936417546335462858915
OFFSET
3,2
REFERENCES
J. Goldman and G.-C. Rota, The number of subspaces of a vector space, pp. 75-83 of W. T. Tutte, editor, Recent Progress in Combinatorics. Academic Press, NY, 1969.
I. P. Goulden and D. M. Jackson, Combinatorial Enumeration. Wiley, NY, 1983, p. 99.
M. Sved, Gaussians and binomials, Ars. Combinatoria, 17A (1984), 325-351.
FORMULA
G.f.: x^3/((1-x)*(1+4*x)*(1-16*x)*(1+64*x)). - Bruno Berselli, Oct 29 2012
a(n) = (-1 + 13*2^(4n-6) + (-1)^n*4^(n-2)*(13-2^(4n-2)))/4875. - Bruno Berselli, Oct 29 2012
a(n) = -51*a(n-1)+884*a(n-2)+3264*a(n-3)-4096*a(n-4). - Wesley Ivan Hurt, Sep 04 2022
MATHEMATICA
Table[QBinomial[n, 3, -4], {n, 3, 20}] (* Vincenzo Librandi, Oct 28 2012 *)
PROG
(Sage) [gaussian_binomial(n, 3, -4) for n in range(3, 17)] # Zerinvary Lajos, May 27 2009
CROSSREFS
Sequence in context: A172742 A172821 A172868 * A221116 A099397 A093251
KEYWORD
sign,easy
AUTHOR
Olivier GĂ©rard, Dec 11 1999
STATUS
approved