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A208387
Number of nX3 0..2 arrays with new values 0..2 introduced in row major order and no element equal to more than two of its immediate leftward or upward or right-upward antidiagonal neighbors
1
5, 117, 3042, 79092, 2056392, 53466192, 1390120992, 36143145792, 939721790592, 24432766555392, 635251930440192, 16516550191444992, 429430304977569792, 11165187929416814592, 290294886164837179392, 7547667040285766664192
OFFSET
1,1
COMMENTS
Column 3 of A208392
LINKS
FORMULA
Empirical: a(n) = 26*a(n-1) for n>2
EXAMPLE
Some solutions for n=4
..0..0..1....0..0..1....0..1..0....0..0..0....0..0..0....0..0..0....0..0..0
..2..0..2....2..0..2....0..1..1....0..1..2....0..1..2....1..2..1....0..1..1
..2..2..0....0..2..2....1..0..2....0..0..0....2..2..1....0..2..2....1..2..0
..0..2..1....2..0..2....1..2..2....1..2..0....2..1..1....0..0..2....1..2..1
CROSSREFS
Sequence in context: A268606 A006221 A265977 * A144998 A257865 A212040
KEYWORD
nonn
AUTHOR
R. H. Hardin Feb 25 2012
STATUS
approved