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A015349
Gaussian binomial coefficient [ n,7 ] for q = -9.
2
1, -4304672, 20846476694116, -99571465386311288480, 476319830905927777714449130, -2278184404047301621409794099651808, 10896505884544222754038383150470776581556, -52117638957586712017437457380440909324731738208
OFFSET
7,2
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.
LINKS
MATHEMATICA
QBinomial[Range[7, 20], 7, -9] (* Harvey P. Dale, Dec 28 2011 *)
PROG
(Sage) [gaussian_binomial(n, 7, -9) for n in range(7, 14)] # Zerinvary Lajos, May 27 2009
(Magma) r:=7; q:=-9; [&*[(1-q^(n-i+1))/(1-q^i): i in [1..r]]: n in [r..15]]; // Vincenzo Librandi, Nov 02 2012
CROSSREFS
Sequence in context: A210308 A205271 A234168 * A210403 A263155 A254266
KEYWORD
sign,easy
AUTHOR
Olivier Gérard, Dec 11 1999
EXTENSIONS
One more term from Harvey P. Dale, Dec 28 2011
STATUS
approved