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A015430 Gaussian binomial coefficient [ n,12 ] for q=-7. 2
1, 12111126301, 171125943656551078651, 2361717858885719498568905414551, 32702835678888952715367233418017870232604, 452622410329553863939387656214689217248493781677804 (list; graph; refs; listen; history; text; internal format)
OFFSET

12,2

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 = 12..110

FORMULA

a(n) = Product_{i=1..12} ((-7)^(n-i+1)-1)/((-7)^i-1) (by definition). - Vincenzo Librandi, Nov 06 2012

MATHEMATICA

Table[QBinomial[n, 12, -7], {n, 12, 20}] (* Vincenzo Librandi, Nov 06 2012 *)

PROG

(Sage) [gaussian_binomial(n, 12, -7) for n in xrange(12, 18)] # Zerinvary Lajos, May 28 2009

(MAGMA) r:=12; q:=-7; [&*[(1-q^(n-i+1))/(1-q^i): i in [1..r]]: n in [r..20]]; // Vincenzo Librandi, Nov 06 2012

CROSSREFS

Sequence in context: A172581 A213534 A202361 * A135496 A287747 A113642

Adjacent sequences:  A015427 A015428 A015429 * A015431 A015432 A015433

KEYWORD

nonn,easy

AUTHOR

Olivier Gérard

STATUS

approved

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Last modified March 18 23:08 EDT 2019. Contains 321305 sequences. (Running on oeis4.)