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A015278 Gaussian binomial coefficient [ n,3 ] for q = -10. 2
1, -909, 918191, -917272809, 917364637191, -917355454462809, 917356372736537191, -917356280909173462809, 917356290091909926537191, -917356289173636281073462809, 917356289265463645628926537191 (list; graph; refs; listen; history; text; internal format)
OFFSET

3,2

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 = 3..200

Index entries for linear recurrences with constant coefficients, signature (-909,91910,909000,-1000000).

FORMULA

G.f.: x^3/((1-x)*(1+10*x)*(1-100*x)*(1+1000*x)). - Bruno Berselli, Oct 30 2012

a(n) = (-1 + 91*10^(2n-3) + (-1)^n*10^(n-2)*(91-10^(2n-1)))/1090089. - Bruno Berselli, Oct 30 2012

a(n) = product(((-10)^(n-i+1)-1)/((-10)^i-1), i=1..3) (by definition). - Vincenzo Librandi, Aug 02 2016

MATHEMATICA

Table[QBinomial[n, 3, -10], {n, 3, 20}] (* Vincenzo Librandi, Oct 28 2012 *)

PROG

(Sage) [gaussian_binomial(n, 3, -10) for n in xrange(3, 14)] # Zerinvary Lajos, May 27 2009

(MAGMA) r:=3; q:=-10; [&*[(1-q^(n-i+1))/(1-q^i): i in [1..r]]: n in [r..20]]; // Vincenzo Librandi, Aug 02 2016

CROSSREFS

Sequence in context: A214001 A252136 A216930 * A210170 A068261 A119520

Adjacent sequences:  A015275 A015276 A015277 * A015279 A015280 A015281

KEYWORD

sign,easy

AUTHOR

Olivier Gérard, Dec 11 1999

STATUS

approved

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Last modified March 22 10:07 EDT 2019. Contains 321421 sequences. (Running on oeis4.)