a(n) = n*B(n-1) + n*(n-1)*B(n-2), where the B(i) are Bell numbers (A000110).
A226855
a(n) = n*B(n-1) + n*(n-1)*B(n-2), where the B(i) are Bell numbers (A000110).
Terms
- a(0) =0a(1) =1a(2) =4a(3) =12a(4) =44a(5) =175a(6) =762a(7) =3605a(8) =18384a(9) =100404a(10) =584070a(11) =3601895a(12) =23451540a(13) =160633681a(14) =1153896772a(15) =8668821600a(16) =67943174000a(17) =554327140739
External references
- oeis: A226855