A212025 - OEIS

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A212025

Number of lower triangular n X n arrays colored with integers 0 upwards introduced in row major order, with no element equal to any horizontal, diagonal or antidiagonal neighbor, and containing the value n(n+1)/2-6

0, 0, 35, 7396, 2655126, 254601542, 9411294829, 187291345391

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

OFFSET

1,3

COMMENTS

Column 5 of A212026

LINKS

Table of n, a(n) for n=1..8.

EXAMPLE

Some solutions for n=4

..0........0........0........0........0........0........0........0

..0.1......1.2......1.2......1.2......1.2......1.2......1.2......1.2