A272499 Number of ordered set partitions of [n] with nondecreasing block sizes and maximal block size equal to nine.
1, 10, 165, 2200, 33605, 492492, 8018010, 131342640, 2321677930, 42349478600, 820275716546, 16515429370440, 350240612952230, 7731410818511380, 178693701272340540, 4296129057927296304, 107666415418378051950, 2801776425029317564400, 75741144900761549630850
Offset: 9
Keywords
Links
- Alois P. Heinz, Table of n, a(n) for n = 9..450
Crossrefs
Column k=9 of A262071.
Programs
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Maple
b:= proc(n, i) option remember; `if`(n=0, 1, `if`(i<1, 0, b(n, i-1)+`if`(i>n, 0, binomial(n, i)*b(n-i, i)))) end: a:= n-> (k-> b(n, k) -b(n, k-1))(9): seq(a(n), n=9..30);
Formula
E.g.f.: x^9 * Product_{i=1..9} (i-1)!/(i!-x^i).