A371487 - OEIS

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A371487

Expansion of e.g.f. Product_{k>=2} 1 / (1 - x^k/k).

1, 0, 1, 2, 12, 44, 380, 2064, 20888, 166368, 1872792, 18917040, 253473792, 3042859104, 45895372224, 661334985024, 11073993828480, 182021308975104, 3418263102400128, 63023443312105728, 1302276954815368704, 26806365139264980480, 603186053115872024064, 13651035149069305878528

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,4

LINKS

Table of n, a(n) for n=0..23.

MAPLE

with(combinat):

b:= proc(n, i) option remember; `if`(n=0, 1, `if`(i<2, 0, add(

(i-1)!^j*b(n-i*j, i-1)*multinomial(n, n-i*j, i$j), j=0..n/i)))

end:

a:= n-> b(n$2):

seq(a(n), n=0..23); # Alois P. Heinz, Mar 26 2024