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Gaussian binomial coefficient [ n,4 ] for q = -4.
3

%I #23 Sep 08 2022 08:44:39

%S 1,205,55965,14107485,3625623645,927257668701,237435704507485,

%T 60779845138496605,15559876852907031645,3983313338565919030365,

%U 1019729183363623510391901,261050608944894743386831965

%N Gaussian binomial coefficient [ n,4 ] for q = -4.

%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="/A015289/b015289.txt">Table of n, a(n) for n = 4..400</a>

%H <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (205,13940,-223040,-839680,1048576).

%F G.f.: -x^4 / ( (x-1)*(256*x-1)*(64*x+1)*(4*x+1)*(16*x-1) ). - _R. J. Mathar_, Aug 03 2016

%t Table[QBinomial[n, 4, -4], {n, 4, 20}] (* _Vincenzo Librandi_, Oct 28 2012 *)

%o (Sage) [gaussian_binomial(n,4,-4) for n in range(4,16)] # _Zerinvary Lajos_, May 27 2009

%o (Magma) r:=4; q:=-4; [&*[(1-q^(n-i+1))/(1-q^i): i in [1..r]]: n in [r..20]]; // _Vincenzo Librandi_, Aug 02 2016

%K nonn,easy

%O 4,2

%A _Olivier GĂ©rard_, Dec 11 1999