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A211913 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, vertical, diagonal or antidiagonal neighbor, and containing the value n(n+1)/2-4 0
0, 0, 10, 802, 27963, 394117, 3243531, 18826250, 85484512, 323341343, 1061434357, 3110902786, 8308425940 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Column 3 of A211916

LINKS

Table of n, a(n) for n=1..13.

EXAMPLE

Some solutions for n=4

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

..1.2......1.2......1.2......1.2......1.2......1.2......1.2......1.2

..0.3.4....3.4.5....3.0.4....3.4.0....3.4.5....0.3.4....0.3.4....3.4.5

..5.6.0.5..0.1.6.7..4.5.6.0..5.6.7.6..2.1.6.3..5.2.6.7..4.5.6.1..1.6.2.1

CROSSREFS

Sequence in context: A221045 A015057 A233170 * A006440 A054944 A272854

Adjacent sequences:  A211910 A211911 A211912 * A211914 A211915 A211916

KEYWORD

nonn

AUTHOR

R. H. Hardin Apr 25 2012

STATUS

approved

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Last modified December 9 08:41 EST 2016. Contains 278971 sequences.