8,2

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.

Sequence in context: A017505 A017637 A058125 this_sequence A103773 A108212 A103124

Adjacent sequences: A015366 A015367 A015368 this_sequence A015370 A015371 A015372

nonn,easy

Olivier Gerard (ogerard(AT)ext.jussieu.fr)