%I #6 Mar 15 2023 14:12:08
%S 7,216,3636,152574,21331380,7767784824,7384820647122,18209251766239734
%N Number of n X n X n triangular 0..6 arrays with no element equal to the difference mod 7 of any two of its neighbors.
%e Some solutions for 4 X 4 X 4
%e .....1........4........2........3........2........1........2........4
%e ....4.4......1.1......2.2......3.3......2.2......1.4......3.2......3.3
%e ...1.4.4....1.1.4....3.3.2....2.2.3....2.2.2....1.1.4....3.2.2....3.3.3
%e ..4.4.1.1..1.1.4.4..3.2.2.2..2.2.3.3..2.2.2.2..4.1.1.4..3.3.2.3..3.2.2.2
%K nonn
%O 1,1
%A _R. H. Hardin_, Aug 07 2011