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A015407
Gaussian binomial coefficient [ n,11 ] for q=-3.
2
1, -132860, 26477735830, -4522934399547980, 811239619864365082573, -143119691677080990521708240, 25388050075285266699527263288120, -4495361402895546052989488899628855120
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} ((-3)^(n-i+1)-1)/((-3)^i-1) (by definition). - Vincenzo Librandi, Nov 05 2012
MATHEMATICA
Table[QBinomial[n, 11, -3], {n, 11, 20}] (* Vincenzo Librandi, Nov 05 2012 *)
PROG
(Sage) [gaussian_binomial(n, 11, -3) for n in range(11, 19)] # Zerinvary Lajos, May 28 2009
(Magma) r:=11; q:=-3; [&*[(1-q^(n-i+1))/(1-q^i): i in [1..r]]: n in [r..25]]; // Vincenzo Librandi, Nov 05 2012
CROSSREFS
Sequence in context: A339535 A319063 A344830 * A204536 A061732 A023046
KEYWORD
sign,easy
STATUS
approved