Obverse convolution A000040**A000040; see Comments.

A374851

Obverse convolution A000040**A000040; see Comments.

Terms

    a(0) =4a(1) =25a(2) =294a(3) =5184a(4) =169000a(5) =6350400a(6) =331218944a(7) =18517766400

External references