OFFSET
6,2
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 6..200
FORMULA
a(n) = Product_{i=1..6} (2^(n-i+1)-1)/(2^i-1), by definition. - Vincenzo Librandi, Aug 03 2016
G.f. with an offset of 0: exp( Sum_{n >= 1} b(7*n)/b(n)*x^n/n ) = 1 + 127*x + 10795*x^2 + ..., where b(n) = A000225(n) = 2^n - 1. - Peter Bala, Jul 01 2025
MATHEMATICA
Table[QBinomial[n, 6, 2], {n, 6, 24}] (* Vincenzo Librandi, Aug 03 2016 *)
PROG
(SageMath) [gaussian_binomial(n, 6, 2) for n in range(6, 20)] # Zerinvary Lajos, May 24 2009
(Magma) r:=6; q:=2; [&*[(1-q^(n-i+1))/(1-q^i): i in [1..r]]: n in [r..20]]; // Vincenzo Librandi, Aug 03 2016
(PARI) r=6; q=2; for(n=r, 30, print1(prod(j=1, r, (1-q^(n-j+1))/(1-q^j)), ", ")) \\ G. C. Greubel, May 30 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
EXTENSIONS
Offset changed by Vincenzo Librandi, Aug 03 2016
STATUS
approved
