A simple context-free grammar in a labeled universe: labeled version of A000245.

A052741

A simple context-free grammar in a labeled universe: labeled version of A000245.

Terms

    a(0) =0a(1) =0a(2) =0a(3) =0a(4) =24a(5) =360a(6) =6480a(7) =141120a(8) =3628800a(9) =107775360a(10) =3632428800a(11) =136994457600

External references