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A231215
Number of (n+1) X (4+1) 0..2 arrays with no element unequal to a strict majority of its horizontal and vertical neighbors, with values 0..2 introduced in row major order.
1
12, 59, 408, 2892, 20027, 139438, 969461, 6745110, 46938804, 326645650, 2273218682, 15819608975, 110091246193, 766140117967, 5331683762978, 37103974744989, 258212125773531, 1796936761480570, 12505151919361622
OFFSET
1,1
COMMENTS
Column 4 of A231219.
FORMULA
Empirical recurrence of order 68 (see link above).
EXAMPLE
Some solutions for n=4:
..0..1..1..2..2....0..1..1..2..2....0..0..1..1..2....0..0..0..0..0
..0..1..1..2..2....0..1..1..2..2....0..0..1..1..2....0..0..1..1..0
..0..1..1..1..2....0..2..2..2..2....0..0..1..1..2....1..1..1..1..0
..0..1..1..1..2....0..2..2..1..1....0..0..1..1..2....1..1..1..1..0
..0..1..1..1..2....0..2..2..1..1....2..2..2..2..2....1..1..1..1..0
CROSSREFS
Cf. A231219.
Sequence in context: A374963 A062477 A048362 * A231340 A099321 A097302
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 05 2013
STATUS
approved