A068286 1/7 the number of colorings of an n X n staggered hexagonal array with 7 colors.

1, 150, 390750, 17684490750, 13905331460469750, 189961376944305892137750, 45086270412704540409445089549750, 185916670055945278226619825124072763091750, 13319483009963134380534870853035913218901916338644750

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, A212194, A212195.

Extensions

a(7)-a(9) from Alois P. Heinz, May 03 2012