Column 3 of triangle A127126.

A127130

Column 3 of triangle A127126.

Terms

    a(0) =1a(1) =4a(2) =30a(3) =284a(4) =3217a(5) =42100a(6) =621936a(7) =10206956a(8) =183946656a(9) =3608229588a(10) =76499111202

External references