1/4 the number of colorings of an n X n staggered hexagonal array with 4 colors.

A068283

1/4 the number of colorings of an n X n staggered hexagonal array with 4 colors.

Terms

    a(0) =1a(1) =12a(2) =264a(3) =11424a(4) =1009608a(5) =185900256a(6) =71883991272

External references