A164745 - OEIS

%I #3 Mar 31 2012 12:35:35

%S 1,17,105,570,3634,30894,360936

%N Number of nXnXn triangular 1..3 arrays with all 1s connected, all 2s connected, all 3s connected, 1 at the top vertex, 2 at the lower left, and 3 at the lower right, and no value having more than 3 identical values adjacent

%e Some solutions for n=4

%e ......1..........1..........1..........1..........1..........1..........1....

%e .....2.1........1.3........2.2........1.3........1.1........3.3........1.1...

%e ....2.1.1......1.1.3......2.3.2......3.1.3......3.3.3......3.2.3......2.2.3..

%e ...2.1.3.3....2.3.3.3....2.3.3.3....2.3.3.3....2.2.3.3....2.2.2.3....2.2.3.3.

%e ------

%e ......1..........1..........1..........1..........1..........1..........1....

%e .....3.1........1.1........2.2........3.1........3.1........1.2........2.1...

%e ....3.1.3......2.2.1......2.3.3......3.1.1......3.3.3......2.2.3......2.2.1..

%e ...2.3.3.3....2.3.3.3....2.2.2.3....2.3.3.3....2.2.2.3....2.2.3.3....2.1.1.3.

%K nonn

%O 2,2

%A _R. H. Hardin_ Aug 24 2009