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A015427
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Gaussian binomial coefficient [ n,12 ] for q=-5.
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2
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1, 203450521, 51740143068101671, 12531617923263572089314671, 3064380040090865325461356053952796, 747900330120650910670378436164144443652796, 182604540723920504029015495725080327984747417027796, 44580616068292567497216163076570130750072904955316534527796
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OFFSET
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12,2
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REFERENCES
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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.
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LINKS
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FORMULA
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a(n) = Product_{i=1..12} ((-5)^(n-i+1)-1)/((-5)^i-1). - Vincenzo Librandi, Nov 06 2012
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MATHEMATICA
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PROG
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(Sage) [gaussian_binomial(n, 12, -5) for n in range(12, 18)] # Zerinvary Lajos, May 28 2009
(Magma) r:=12; q:=-5; [&*[(1-q^(n-i+1))/(1-q^i): i in [1..r]]: n in [r..20]]; // Vincenzo Librandi, Nov 06 2012
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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