OFFSET
9,2
LINKS
Alois P. Heinz, Table of n, a(n) for n = 9..450
Andrew V. Sills, Integer Partitions Probability Distributions, arXiv:1912.05306 [math.CO], 2019.
Wikipedia, Permutation
MAPLE
b:= proc(n, i, t) option remember; `if`(n=0, [1, 0], `if`(i>n, 0,
add((p-> p+`if`(t>0 and t-j<1, [0, p[1]*i], 0))((i-1)!^j*
b(n-i*j, i+1, max(0, t-j))/j!*combinat[multinomial]
(n, i$j, n-i*j)), j=0..n/i)))
end:
a:= n-> b(n, 1, 9)[2]:
seq(a(n), n=9..25);
CROSSREFS
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Mar 02 2020
STATUS
approved