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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
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: A256622 A359344 A022251 * A027570 A202362 A204058
KEYWORD
sign,easy
AUTHOR
STATUS
approved

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Last modified March 28 04:13 EDT 2024. Contains 371235 sequences. (Running on oeis4.)