a(n) = Sum_{k=0..n-1} Bell(k), where the Bell numbers Bell(k) are given in A000110.
A005001
a(n) = Sum_{k=0..n-1} Bell(k), where the Bell numbers Bell(k) are given in A000110.
Terms
- a(0) =0a(1) =1a(2) =2a(3) =4a(4) =9a(5) =24a(6) =76a(7) =279a(8) =1156a(9) =5296a(10) =26443a(11) =142418a(12) =820988a(13) =5034585a(14) =32679022a(15) =223578344a(16) =1606536889a(17) =12086679036a(18) =94951548840a(19) =777028354999
External references
- oeis: A005001