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A252905
Number of (n+2)X(1+2) 0..3 arrays with every consecutive three elements in every row and column having exactly 2 distinct values, in every diagonal 1 or 2 distinct values, in every antidiagonal 2 or 3 distinct values, and new values 0 upwards introduced in row major order
1
238, 1125, 5567, 28642, 148002, 771768, 4034881, 21118867, 110669161, 580192543, 3042199896, 15954252572, 83676184647, 438866555650, 2301856594765, 12073355842878, 63325661038166, 332149215192824, 1742159173884376
OFFSET
1,1
COMMENTS
Column 1 of A252910
FORMULA
Empirical recurrence of order 63 (see link above)
EXAMPLE
Some solutions for n=2
..0..0..1....0..1..0....0..0..1....0..1..1....0..1..0....0..1..1....0..1..1
..0..2..2....0..2..2....2..2..1....2..2..1....0..1..1....1..0..1....0..1..1
..2..0..2....3..2..2....2..0..2....2..1..2....1..0..1....0..1..0....2..0..0
..0..0..3....0..1..0....3..2..2....0..2..2....0..0..2....0..1..1....2..0..0
CROSSREFS
Sequence in context: A124169 A264885 A252910 * A122266 A286213 A251404
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 24 2014
STATUS
approved