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%I #26 Sep 08 2022 08:44:39
%S 1,-85,14535,-1652145,225683007,-28005209505,3642010817055,
%T -462535373765985,59438516325245343,-7593183562134412385,
%U 972884994173649887135,-124468028808034701006945
%N Gaussian binomial coefficient [ n,7 ] for q = -2.
%D 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.
%D I. P. Goulden and D. M. Jackson, Combinatorial Enumeration. Wiley, NY, 1983, p. 99.
%D M. Sved, Gaussians and binomials, Ars. Combinatoria, 17A (1984), 325-351.
%H G. C. Greubel, <a href="/A015338/b015338.txt">Table of n, a(n) for n = 7..450</a>[Terms 7 through 200 were computed by Vincenzo Librandi; terms 201 to 450 by G. C. Greubel, Nov 06 2016]
%t Table[QBinomial[n, 7, -2], {n, 7, 20}] (* _Vincenzo Librandi_, Oct 29 2012 *)
%o (Sage) [gaussian_binomial(n,7,-2) for n in range(7,19)] # _Zerinvary Lajos_, May 27 2009
%o (Magma) /* By definition: */ r:=7; q:=-2; [&*[(1-q^(n-i+1))/(1-q^i): i in [1..r]]: n in [r..20]]; // _Bruno Berselli_, Oct 30 2012
%Y Diagonal k=7 of the triangular array A015109. See there for further references and programs. - _M. F. Hasler_, Nov 04 2012
%K sign,easy
%O 7,2
%A _Olivier Gérard_, Dec 11 1999
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