Column 1 of triangle A107719.

A107721

Column 1 of triangle A107719.

Terms

    a(0) =1a(1) =2a(2) =13a(3) =131a(4) =1741a(5) =28451a(6) =549757a(7) =12247211a(8) =308953453a(9) =8706012827a(10) =271093643293

External references