A223407 - OEIS

A223407

4X4X4 triangular graph without horizontal edges coloring a rectangular array: number of n X n 0..9 arrays where 0..9 label nodes of a graph with edges 0,1 0,2 1,3 1,4 2,4 2,5 3,6 3,7 4,7 4,8 5,8 5,9 and every array movement to a horizontal or vertical neighbor moves along an edge of this graph

%I #6 Dec 18 2015 18:18:30

%S 10,132,10496,4222748,8949958604,95513129162264,5291975389978126280,

%T 1474413700790967027512272,2128059896246198793880831622720,

%U 15441445504387727838090586696442043920

%N 4X4X4 triangular graph without horizontal edges coloring a rectangular array: number of n X n 0..9 arrays where 0..9 label nodes of a graph with edges 0,1 0,2 1,3 1,4 2,4 2,5 3,6 3,7 4,7 4,8 5,8 5,9 and every array movement to a horizontal or vertical neighbor moves along an edge of this graph

%C Diagonal of A223415

%H R. H. Hardin, <a href="/A223407/b223407.txt">Table of n, a(n) for n = 1..11</a>

%e Some solutions for n=3

%e ..4..7..3....8..4..1....2..4..1....5..8..4....1..4..1....1..3..7....4..2..0

%e ..1..4..7....4..8..4....4..7..3....8..4..2....0..2..4....3..7..4....2..0..1

%e ..4..7..4....2..4..2....1..3..7....4..2..5....2..4..8....1..4..8....0..2..4

%K nonn

%O 1,1

%A _R. H. Hardin_ Mar 20 2013