A223368 - OEIS

%I #6 Mar 15 2023 11:52:56

%S 45984,20537766,11391019146,6710970374274,4058501783492178,

%T 2480736960312897168,1524391185435213940170,939167584646744478258996,

%U 579454062205580451233813394,357802181014544893364679825516

%N 6 X 6 X 6 triangular graph coloring a rectangular array: number of n X 6 0..20 arrays where 0..20 label nodes of the fully triangulated graph and every array movement to a horizontal or vertical neighbor moves along an edge of this graph.

%C Column 6 of A223370.

%H R. H. Hardin, <a href="/A223368/b223368.txt">Table of n, a(n) for n = 1..210</a>

%e Some solutions for n=3

%e ..1..0..2..5..2..0....1..0..2..4..5..8....1..0..2..4..2..5....1..0..2..4..5..9

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

%e ..1..0..2..5..2..5....1..0..1..2..4..1....1..0..2..1..2..4....1..0..1..4..8..9

%e Vertex neighbors:

%e 0 -> 1 2

%e 1 -> 0 2 3 4

%e 2 -> 0 1 4 5

%e 3 -> 1 4 6 7

%e 4 -> 1 2 3 5 7 8

%e 5 -> 2 4 8 9

%e 6 -> 3 7 10 11

%e 7 -> 3 4 6 8 11 12

%e 8 -> 4 5 7 9 12 13

%e 9 -> 5 8 13 14

%e 10 -> 6 11 15 16

%e 11 -> 6 7 10 12 16 17

%e 12 -> 7 8 11 13 17 18

%e 13 -> 8 9 12 14 18 19

%e 14 -> 9 13 19 20

%e 15 -> 10 16

%e 16 -> 10 11 15 17

%e 17 -> 11 12 16 18

%e 18 -> 12 13 17 19

%e 19 -> 13 14 18 20

%e 20 -> 14 19

%Y Cf. A223370.

%K nonn

%O 1,1

%A _R. H. Hardin_, Mar 19 2013