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A015385 Gaussian binomial coefficient [ n,9 ] for q=-13. 23
1, -9847035132, 105044442632566365137, -1113436927250681654567602842120, 11807854622717155763702496765310830475383, -125216049699851612689080581288579246248342359563916 (list; graph; refs; listen; history; text; internal format)
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..110

Index entries related to Gaussian binomial coefficients.

FORMULA

a(n) = Product_{i=1..9} ((-13)^(n-i+1)-1)/((-13)^i-1). - M. F. Hasler, Nov 03 2012

MATHEMATICA

Table[QBinomial[n, 9, -13], {n, 9, 20}] (* Vincenzo Librandi, Nov 04 2012 *)

PROG

(PARI) A015385(n, r=9, q=-13)=prod(i=1, r, (q^(n-i+1)-1)/(q^i-1)) \\ M. F. Hasler, Nov 03 2012

(MAGMA) r:=9; q:=-13; [&*[(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,r] for q=-13: A015265 (r=2), A015286 (r=3), A015303 (r=4), A015321 (r=5), A015337 (r=6), A015355 (r=7), A015370 (r=8), A015402 (r=10), A015422 (r=11), A015438 (r=12). - M. F. Hasler, Nov 03 2012

Cf. Gaussian binomial coefficients [n, 9] for q = -2..-13: A015371, A015375, A015376, A015377, A015378, A015379, A015380, A015381, A015382, A015383, A015384. - Vincenzo Librandi, Nov 04 2012

Sequence in context: A130428 A256622 A022251 * A027570 A202362 A204058

Adjacent sequences:  A015382 A015383 A015384 * A015386 A015387 A015388

KEYWORD

sign,easy

AUTHOR

Olivier Gérard

STATUS

approved

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Last modified March 23 09:20 EDT 2019. Contains 321424 sequences. (Running on oeis4.)