A290038 Number of set partitions of [n] having exactly nine blocks of size > 1.
34459425, 2618916300, 108030297375, 3211227869850, 77083218186975, 1588144599241200, 29158562820672285, 489227666491814250, 7636058324659014250, 112346788172994575200, 1573773827894456037850, 21155069633041246602700, 274588861338588612866050
Offset: 18
Links
- Alois P. Heinz, Table of n, a(n) for n = 18..1000
- Wikipedia, Partition of a set
- Index entries for linear recurrences with constant coefficients, order 55.
Formula
E.g.f.: (exp(x)-x-1)^9/9!*exp(x).
a(0) = a(1) = 0, for n>1 a(n) = 10*a(n-1) + (n-1)*A290037(n-2). - Ray Chandler, Jul 21 2017