10,2

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: A129250 A121841 A096630 this_sequence A129475 A017290 A017398

Adjacent sequences: A015396 A015397 A015398 this_sequence A015400 A015401 A015402

nonn,easy

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