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Gaussian binomial coefficients [ n,4 ] for q = 9.
1

%I #14 Sep 08 2022 08:44:46

%S 1,7381,49031983,322140667123,2113887057661126,13869447829832637406,

%T 90997618413507253345810,597035499217287155085549610,

%U 3917150001348391097251303957615,25700421225173962543056800181928315,168620463706718874134703442098874261321

%N Gaussian binomial coefficients [ n,4 ] for q = 9.

%D F. J. MacWilliams and N. J. A. Sloane, The Theory of Error-Correcting Codes, Elsevier-North Holland, 1978, p. 698.

%H Vincenzo Librandi, <a href="/A022255/b022255.txt">Table of n, a(n) for n = 4..200</a>

%F a(n) = Product_{i=1..4} (9^(n-i+1)-1)/(9^i-1), by definition. - _Vincenzo Librandi_, Aug 04 2016

%t Table[QBinomial[n, 4, 9], {n, 4, 20}] (* _Vincenzo Librandi_, Aug 04 2016 *)

%o (Sage) [gaussian_binomial(n,4,9) for n in range(4,15)] # _Zerinvary Lajos_, May 27 2009

%o (Magma) r:=4; q:=9; [&*[(1-q^(n-i+1))/(1-q^i): i in [1..r]]: n in [r..20]]; // _Vincenzo Librandi_, Aug 04 2016

%K nonn

%O 4,2

%A _N. J. A. Sloane_.

%E Offset changed by _Vincenzo Librandi_, Aug 04 2016