|
| |
|
|
A088312
|
|
Number of sets of lists (cf. A000262) with even number of lists.
|
|
1
| |
|
|
1, 6, 37, 260, 2101, 19362, 201097, 2326536, 29668681, 413257790, 6238931821, 101415565836
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 2,2
|
|
|
LINKS
| N. Heninger, E. M. Rains and N. J. A. Sloane, On the Integrality of n-th Roots of Generating Functions, J. Combinatorial Theory, Series A, 113 (2006), 1732-1745.
N. J. A. Sloane, LAH transform
|
|
|
FORMULA
| E.g.f.: cosh(x/(1-x)). a(n) = Sum_{k=1.. floor(n/2)} n!/(2*k)!*binomial(n-1, 2*k-1).
|
|
|
CROSSREFS
| Cf. A027187, A024429, A024430, A001710.
Sequence in context: A192238 A140712 A079751 * A012364 A012719 A179515
Adjacent sequences: A088309 A088310 A088311 * A088313 A088314 A088315
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| Vladeta Jovovic (vladeta(AT)eunet.rs), Nov 05 2003
|
| |
|
|
