First differences of A265906; second differences of A265905.

A275953

First differences of A265906; second differences of A265905.

Terms

    a(0) =6a(1) =30a(2) =204a(3) =1446a(4) =11550a(5) =108204a(6) =1091526a(7) =11998830a(8) =146864484a(9) =1920044166a(10) =26872081230a(11) =407766664284

External references