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%I #20 Sep 08 2022 08:44:39
%S 1,90909091,9182736463728191,917356290091909926537191,
%T 91744803489448201844894398447191,
%U 9174388605059687035653977786959679347191,917439777945737474914267633276565557306870347191
%N Gaussian binomial coefficient [ n,8 ] for q=-10.
%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 Vincenzo Librandi, <a href="/A015367/b015367.txt">Table of n, a(n) for n = 8..100</a>
%F a(n) = Product_{i=1..8} ((-10)^(n-i+1)-1)/((-10)^i-1). - _M. F. Hasler_, Nov 03 2012
%t Table[QBinomial[n, 8, -10], {n, 8, 14}] (* _Vincenzo Librandi_, Nov 03 2012 *)
%o (Sage) [gaussian_binomial(n,8,-10) for n in range(8,14)] # _Zerinvary Lajos_, May 25 2009
%o (Magma) r:=8; q:=-10; [&*[(1-q^(n-i+1))/(1-q^i): i in [1..r]]: n in [r..18]]; // _Vincenzo Librandi_, Nov 03 2012
%o (PARI) A015367(n,r=8,q=-10)=prod(i=1,r,(q^(n-i+1)-1)/(q^i-1)) \\ _M. F. Hasler_, Nov 03 2012
%Y Cf. Gaussian binomial coefficients [n,8] for q=-2..-13: A015356, A015357, A015359, A015360, A015361, A015363, A015364, A015365, A015368, A015369, A015370. - _M. F. Hasler_, Nov 03 2012
%K nonn,easy
%O 8,2
%A _Olivier Gérard_
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