A006109 Gaussian binomial coefficient [ n,n/2 ] for q=4. (Formerly M3917)

1, 1, 5, 21, 357, 5797, 376805, 24208613, 6221613541, 1594283908581, 1634141006295525, 1673768626404966885, 6857430062381149327845, 28089747579101385828291045, 460250514083576206796548772325, 7540859480106603961931048583270885

Offset

0,3

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.

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

M. Sved, Gaussians and binomials, Ars. Combinatoria, 17A (1984), 325-351.

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..80

M. Sved, Gaussians and binomials, Ars. Combinatoria, 17A (1984), 325-351. (Annotated scanned copy)

Mathematica

Table[QBinomial[n, Floor[n/2], 4], {n, 0, 20}] (* Vincenzo Librandi, Aug 13 2016 *)

Crossrefs

Sequence in context: A301797 A015461 A101694 * A009732 A009758 A143503

Adjacent sequences: A006106 A006107 A006108 * A006110 A006111 A006112

Keyword

nonn

Author

N. J. A. Sloane

Status

approved