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A015434
Gaussian binomial coefficient [ n,12 ] for q=-11.
2
1, 2876892678661, 9104162632986302495960347, 28551311330859170052594978984538703567, 89612366318560505321323986969057938917191132920348, 281240247078624326614268823428029385995576471270476701478391628
OFFSET
12,2
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(((-11)^(n-i+1)-1)/((-11)^i-1), i=1..12) (by definition). - Vincenzo Librandi, Nov 06 2012
MATHEMATICA
Table[QBinomial[n, 12, -11], {n, 12, 20}] (* Vincenzo Librandi, Nov 06 2012 *)
PROG
(Sage) [gaussian_binomial(n, 12, -11) for n in range(12, 17)] # Zerinvary Lajos, May 28 2009
(Magma) r:=12; q:=-11; [&*[(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: A233496 A233617 A323052 * A017292 A017400 A017664
KEYWORD
nonn,easy
AUTHOR
Olivier Gérard, Dec 11 1999
STATUS
approved