Column 1 of triangle Q = A135885; also equals column 0 of Q^2.

A135886

Column 1 of triangle Q = A135885; also equals column 0 of Q^2.

Terms

    a(0) =1a(1) =4a(2) =20a(3) =126a(4) =980a(5) =9186a(6) =101492a(7) =1296934a(8) =18868652a(9) =308478492a(10) =5605768476a(11) =112198139500

External references