a(n) = Sum_{k=1..n} C(n-1,k-1) * S2(n,k) * 2^(n-k) for n>0, a(0)=1, where S2(n,k) = A048993(n,k) are Stirling numbers of the 2nd kind.

A245059

a(n) = Sum_{k=1..n} C(n-1,k-1) * S2(n,k) * 2^(n-k) for n>0, a(0)=1, where S2(n,k) = A048993(n,k) are Stirling numbers of the 2nd kind.

Terms

    a(0) =1a(1) =1a(2) =3a(3) =17a(4) =129a(5) =1177a(6) =12463a(7) =149053a(8) =1975473a(9) =28628865a(10) =449059179a(11) =7562334793a(12) =135837896769

External references