Second column (m=2) of triangle S2hat(-1) = A144270.

A144272

Second column (m=2) of triangle S2hat(-1) = A144270.

Terms

    a(0) =1a(1) =1a(2) =4a(3) =18a(4) =129a(5) =1095a(6) =11880a(7) =149940a(8) =2218545a(9) =37147005a(10) =699281100a(11) =14561835750a(12) =332913128625

External references