Second column of triangle A055864.

A055865

Second column of triangle A055864.

Terms

    a(0) =0a(1) =2a(2) =12a(3) =100a(4) =1080a(5) =14406a(6) =229376a(7) =4251528a(8) =90000000a(9) =2143588810a(10) =56757583872

External references