A068273 - OEIS

%I #12 Jun 25 2017 17:10:59

%S 1,80,65600,552093440,47694893373440,42294602754348892160,

%T 384991688574716612134952960,35972520655083241381477879725916160,

%U 34501934082562716587411029908821592862883840,339679276508747763623945195020701159657032777565470720

%N 1/6 the number of colorings of an n X n rhombic hexagonal array with 6 colors.

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

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

%K nonn

%O 1,2

%A _R. H. Hardin_, Feb 24 2002

%E a(7)-a(9) from _Alois P. Heinz_, May 02 2012

%E a(10) from _Andrew Howroyd_, Jun 25 2017