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: A014497 A111346 A136608 this_sequence A081640 A125565 A104334

Adjacent sequences: A015361 A015362 A015363 this_sequence A015365 A015366 A015367

nonn,easy

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