a(n) = B(n)*P(n), where B(n) are Bell numbers (A000110) and P(n) are numbers of arrangements of a set of n elements (A000522).

A064312

a(n) = B(n)*P(n), where B(n) are Bell numbers (A000110) and P(n) are numbers of arrangements of a set of n elements (A000522).

Terms

    a(0) =1a(1) =2a(2) =10a(3) =80a(4) =975a(5) =16952a(6) =397271a(7) =12014900a(8) =453748140a(9) =20859612270

External references