A068274 1/7 the number of colorings of an n X n rhombic hexagonal array with 7 colors.

1, 150, 390750, 17684490750, 13905324304629750, 189961153574587570713750, 45086187185888873181881847687750, 185916202268606023083570420269986443660750, 13319440571031747382017558973436842742801064314274750

Offset: 1

Author

R. H. Hardin, Feb 24 2002

Keywords

• nonn

Comments

Terms for rhombic- and staggered- hexagonal arrays are the same for n in 1..4.

Crossrefs

Cf. A068239-A068305, A000332, A002417, A027441, A212162, A212163.

Extensions

a(7)-a(9) from Alois P. Heinz, May 02 2012