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A015345
Gaussian binomial coefficient [ n,7 ] for q = -6.
2
1, -239945, 69088371619, -19251196169490725, 5393264335151280477835, -1509574711680960125598763925, 422593364163884169440003098013995, -118298673397216914972187267242547690325, 33116077152651051199781730118147946460139435
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
Index entries for linear recurrences with constant coefficients, signature (-239945,11514768594,89124308917560,-115609163009731776,-24949102541146076160,902345215627683201024,5263661621405464657920,-6140942214464815497216)
FORMULA
G.f.: x^7 / ( (x-1)*(279936*x+1)*(216*x+1)*(36*x-1)*(7776*x+1)*(1296*x-1)*(6*x+1)*(46656*x-1) ). - R. J. Mathar, Sep 02 2016
MATHEMATICA
Table[QBinomial[n, 7, -6], {n, 7, 20}] (* Vincenzo Librandi, Nov 02 2012 *)
PROG
(Sage) [gaussian_binomial(n, 7, -6) for n in range(7, 15)] # Zerinvary Lajos, May 27 2009
(Magma) r:=7; q:=-6; [&*[(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: A237396 A234547 A234709 * A187960 A190388 A249194
KEYWORD
sign,easy
AUTHOR
Olivier Gérard, Dec 11 1999
STATUS
approved