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A015421
Gaussian binomial coefficient [ n,11 ] for q=-12.
2
1, -685853880635, 513158776998704708174485, -381060745537275503024171826161834795, 283144978428780810444903027180667803787005364693, -210378243627879792478862753186483140572522717247026752860715
OFFSET
11,2
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
FORMULA
a(n) = Product_{i=1..11} ((-12)^(n-i+1)-1)/((-12)^i-1)). - Vincenzo Librandi, Nov 06 2012
MATHEMATICA
Table[QBinomial[n, 11, -12], {n, 11, 20}] (* Vincenzo Librandi, Nov 06 2012 *)
PROG
(Sage) [gaussian_binomial(n, 11, -12) for n in range(11, 16)] # Zerinvary Lajos, May 28 2009
(Magma) r:=11; q:=-12; [&*[(1-q^(n-i+1))/(1-q^i): i in [1..r]]: n in [r..20]]; // Vincenzo Librandi, Nov 06 2012
CROSSREFS
Sequence in context: A297006 A230559 A105302 * A335336 A180612 A092382
KEYWORD
sign,easy
STATUS
approved