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A022197
Gaussian binomial coefficients [ n,6 ] for q = 3.
1
1, 1093, 896260, 678468820, 500777836042, 366573514642546, 267598665689058580, 195168545232713290660, 142299528422960399756323, 103741619611085612124067759, 75628919722004322604209288760, 55133793282290501540016988429720
OFFSET
6,2
LINKS
FORMULA
G.f.: x^6/((1-x)*(1-3*x)*(1-9*x)*(1-27*x)*(1-81*x)*(1-243*x)*(1-729*x)). - Vincenzo Librandi, Aug 07 2016
a(n) = Product_{i=1..6} (3^(n-i+1)-1)/(3^i-1), by definition. - Vincenzo Librandi, Aug 07 2016
MATHEMATICA
Table[QBinomial[n, 6, 3], {n, 6, 20}] (* Vincenzo Librandi, Aug 07 2016 *)
PROG
(Sage) [gaussian_binomial(n, 6, 3) for n in range(6, 18)] # Zerinvary Lajos, May 25 2009
(Magma) r:=6; q:=3; [&*[(1-q^(n-i+1))/(1-q^i): i in [1..r]]: n in [r..20]]; // Vincenzo Librandi, Aug 07 2016
(PARI) r=6; q=3; for(n=r, 30, print1(prod(j=1, r, (1-q^(n-j+1))/(1-q^j)), ", ")) \\ G. C. Greubel, May 30 2018
CROSSREFS
Sequence in context: A115192 A307220 A091674 * A259909 A124122 A163561
KEYWORD
nonn,easy
EXTENSIONS
Offset changed by Vincenzo Librandi, Aug 07 2016
STATUS
approved