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A015409 Gaussian binomial coefficient [ n,11 ] for q=-5. 2
1, -40690104, 2069605714586046, -100252942972187432169704, 4903008044094795843516454343421, -239328104658006678585444195424892284704, 11686690558465291130135333443500921076518590296, -570631883336806742698184435808699328319904985223284704 (list; graph; refs; listen; history; text; internal format)
OFFSET

11,2

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 = 11..140

FORMULA

a(n) = Product_{i=1..11} ((-5)^(n-i+1)-1)/((-5)^i-1) (by definition). - Vincenzo Librandi, Nov 05 2012

MATHEMATICA

Table[QBinomial[n, 11, -5], {n, 11, 20}] (* Vincenzo Librandi, Nov 05 2012 *)

PROG

(Sage) [gaussian_binomial(n, 11, -5) for n in range(11, 17)] # Zerinvary Lajos, May 28 2009

(MAGMA) r:=11; q:=-5; [&*[(1-q^(n-i+1))/(1-q^i): i in [1..r]]: n in [r..25]]; // Vincenzo Librandi, Nov 05 2012

CROSSREFS

Sequence in context: A017361 A017481 A017613 * A178204 A130681 A261658

Adjacent sequences:  A015406 A015407 A015408 * A015410 A015411 A015412

KEYWORD

sign,easy

AUTHOR

Olivier Gérard

STATUS

approved

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Last modified January 21 21:30 EST 2020. Contains 331128 sequences. (Running on oeis4.)