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A252805
Number of (n+2) X (2+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
155, 259, 488, 369, 702, 2301, 1864, 3971, 13398, 11033, 23486, 78603, 66024, 139811, 462262, 397385, 835886, 2723707, 2404648, 5019491, 16081590, 14635481, 30289406, 95177547, 89643528, 183775811, 564866134, 552873161, 1121777966, 3363196795
OFFSET
1,1
COMMENTS
Column 2 of A252811.
LINKS
FORMULA
Empirical: a(n) = a(n-1) +13*a(n-3) -13*a(n-4) -43*a(n-6) +43*a(n-7) +7*a(n-9) -7*a(n-10) for n>16.
EXAMPLE
Some solutions for n=2
..0..1..2..0....0..1..2..0....0..1..2..0....0..1..2..3....0..1..2..3
..3..0..2..1....3..0..2..4....1..0..2..3....1..2..4..0....1..3..0..2
..2..2..2..2....2..2..2..2....2..2..2..2....3..4..0..1....2..0..3..1
..0..1..2..0....1..4..2..0....4..3..2..0....0..3..1..2....4..2..1..0
CROSSREFS
Cf. A252811.
Sequence in context: A214472 A259379 A122475 * A089256 A112136 A119609
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 22 2014
STATUS
approved