a(n) = Sum(((k-1)/2)*k!*Stirling_2(n,k),k=1..n).

A083411

a(n) = Sum(((k-1)/2)*k!*Stirling_2(n,k),k=1..n).

Terms

    a(0) =0a(1) =1a(2) =9a(3) =79a(4) =765a(5) =8311a(6) =100989a(7) =1362439a(8) =20246445a(9) =328972471a(10) =5805917469a(11) =110645911399

External references