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A252807
Number of (n+2) X (4+2) 0..4 arrays with every consecutive three elements in every row and column not having exactly two distinct values, and in every diagonal and antidiagonal having exactly two distinct values, and new values 0 upwards introduced in row major order.
1
752, 369, 551, 742, 1625, 2795, 3763, 8275, 14320, 19355, 42636, 73806, 99746, 219780, 380509, 514272, 1133211, 1961985, 2651701, 5843149, 10116582, 13672981, 30129126, 52164340, 70502284, 155355518, 268976251, 363532650, 801063517
OFFSET
1,1
COMMENTS
Column 4 of A252811.
LINKS
FORMULA
Empirical: a(n) = 6*a(n-3) -4*a(n-6) -2*a(n-9) +a(n-12) for n>15.
EXAMPLE
Some solutions for n=2
..0..1..2..0..3..4....0..1..2..0..3..2....0..1..2..3..1..2....0..1..2..3..1..2
..0..2..1..0..4..1....4..0..2..3..0..2....1..0..2..1..3..2....2..2..2..2..2..2
..0..0..0..0..0..0....2..2..2..2..2..2....2..2..2..2..2..2....1..3..2..1..4..2
..0..1..4..0..1..3....1..3..2..0..1..2....3..1..2..0..4..2....3..0..2..4..1..2
CROSSREFS
Cf. A252811.
Sequence in context: A373206 A020391 A355318 * A332000 A223447 A200211
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 22 2014
STATUS
approved