a(n) = n!*Sum_{k=0..n} bell(k+1)/k!, n=0,1..., where bell(n) are the Bell numbers, cf. A000110.

A113060

a(n) = n!*Sum_{k=0..n} bell(k+1)/k!, n=0,1..., where bell(n) are the Bell numbers, cf. A000110.

Terms

    a(0) =1a(1) =3a(2) =11a(3) =48a(4) =244a(5) =1423a(6) =9415a(7) =70045a(8) =581507a(9) =5349538a(10) =54173950a(11) =600127047a(12) =7229169001a(13) =94170096335

External references