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%I #17 Sep 08 2022 08:44:46
%S 1,349525,97734250405,26027119554103525,6849609413493939400165,
%T 1797339217481455290934231525,471276749188750005563056686387685,
%U 123549912998815788062283863044996567525
%N Gaussian binomial coefficients [ n,9 ] for q = 4.
%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="/A022208/b022208.txt">Table of n, a(n) for n = 9..190</a>
%F G.f.: x^9/((1-x)*(1-4*x)*(1-16*x)*(1-64*x)*(1-256*x)*(1-1024*x)*(1-4096*x)*(1-16384*x)*(1-65536*x)*(1-262144*x)). - _Vincenzo Librandi_, Aug 11 2016
%F a(n) = Product_{i=1..9} (4^(n-i+1)-1)/(4^i-1), by definition. - _Vincenzo Librandi_, Aug 11 2016
%t Table[QBinomial[n, 9, 4], {n, 9, 20}] (* _Vincenzo Librandi_, Aug 11 2016 *)
%o (Sage) [gaussian_binomial(n,9,4) for n in range(9,17)] # _Zerinvary Lajos_, May 25 2009
%o (Magma) r:=9; q:=4; [&*[(1-q^(n-i+1))/(1-q^i): i in [1..r]]: n in [r..20]]; // _Vincenzo Librandi_, Aug 11 2016
%o (PARI) r=9; q=4; for(n=r,30, print1(prod(j=1,r,(1-q^(n-j+1))/(1-q^j)), ", ")) \\ _G. C. Greubel_, Jun 04 2018
%K nonn,easy
%O 9,2
%A _N. J. A. Sloane_
%E Offset changed by _Vincenzo Librandi_, Aug 11 2016
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