A208093 - OEIS

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A208093

Number of nX3 nonnegative integer arrays with new values 0 upwards introduced in row major order and no element equal to any horizontal, diagonal or antidiagonal neighbor (colorings ignoring permutations of colors)

2, 30, 1573, 192328, 43366459, 15769674462, 8494585220016, 6391850672195207, 6435536606760976374, 8388789053759733374255, 13792349692923790472807338, 28002764873470436036725295426, 68986219453948522377865096287773

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

Column 3 of A208096

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..16

EXAMPLE

Some solutions for n=4

..0..1..2....0..1..0....0..1..0....0..1..2....0..1..0....0..1..0....0..1..0

..0..1..2....2..1..0....0..1..0....0..3..0....0..1..0....2..3..0....0..1..0

..0..1..0....3..1..2....0..1..0....0..1..0....2..1..2....0..3..0....0..1..2