A015382 Gaussian binomial coefficient [ n,9 ] for q=-10.

1, -909090909, 918273645463728191, -917356289173636281073462809, 917448033977125729275307703398447191, -917438859588520669588272049420660231320652809, 917439777028298615325746963688293507886210115870347191

Offset

9,2

References

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.

I. P. Goulden and D. M. Jackson, Combinatorial Enumeration. Wiley, NY, 1983, p. 99.

M. Sved, Gaussians and binomials, Ars. Combinatoria, 17A (1984), 325-351.

Links

Vincenzo Librandi, Table of n, a(n) for n = 9..120

Formula

a(n) = Product_{i=1..9} ((-10)^(n-i+1)-1)/((-10)^i-1). - Vincenzo Librandi, Nov 04 2012

Mathematica

Table[QBinomial[n, 9, -10], {n, 9, 20}] (* Vincenzo Librandi, Nov 04 2012 *)

Prog

(Magma) r:=9; q:=-10; [&*[(1-q^(n-i+1))/(1-q^i): i in [1..r]]: n in [r..20]]; // Vincenzo Librandi, Nov 04 2012

Crossrefs

Cf. Gaussian binomial coefficients [n, 9] for q = -2..-13: A015371, A015375, A015376, A015377, A015378, A015379, A015380, A015381, A015383, A015384, A015385. - Vincenzo Librandi, Nov 04 2012

Sequence in context: A189229 A051470 A076135 * A115385 A186805 A122532

Adjacent sequences: A015379 A015380 A015381 * A015383 A015384 A015385

Keyword

sign,easy

Author

Olivier Gérard

Status

approved