A246255 Number of permutations of [n] with exactly ten occurrences of the consecutive step pattern up, down, down.

62671742039942099631403299, 18231157381733294406542318214, 3087040831300287487055787449994, 394974982016287093640971012693311, 42334746925643499979072751981842422, 4013581941216432516413056735995683706, 347925850343780865770905714211197525182

Offset: 31

Author

Alois P. Heinz, Aug 20 2014

Keywords

• nonn

Links

• Alois P. Heinz, Table of n, a(n) for n = 31..160

Crossrefs

Column k=10 of A242819.

Formula

a(n) ~ c * (3*sqrt(3)/(2*Pi))^n * n! * n^10, where c = 0.00000000000652802483581788974... = c0 * (c0-1)^10 / (3^10 * 10!), and c0 = (1 + exp(Pi/sqrt(3))) * sqrt(3) / (2*Pi). - Vaclav Kotesovec, Aug 26 2014