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A201623
Number of nX6 0..3 arrays with rows and columns lexicographically nondecreasing and every element equal to at least one horizontal or vertical neighbor
0
26, 2271, 256836, 45733593, 8368969235, 1492809994673, 242036871702096, 35298906093734951, 4642502137893927659, 554913226364951538300, 60802653561518861509758, 6157866184324500142914732
OFFSET
1,1
COMMENTS
Column 6 of A201625
EXAMPLE
Some solutions for n=2
..0..0..0..2..2..2....0..0..0..1..2..2....0..0..0..0..0..3....0..0..0..0..2..2
..0..2..2..0..0..0....3..3..3..1..3..3....0..0..0..2..2..3....2..2..2..2..2..2
CROSSREFS
Sequence in context: A266030 A103642 A363990 * A087616 A177636 A232159
KEYWORD
nonn
AUTHOR
R. H. Hardin Dec 03 2011
STATUS
approved