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A252806
Number of (n+2)X(3+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
357, 488, 1337, 551, 2068, 6961, 2891, 10687, 35835, 15328, 56023, 186554, 81798, 294256, 971782, 438093, 1549042, 5068959, 2354313, 8172677, 26476065, 12695662, 43221349, 138494624, 68704164, 229160414, 725637116, 373152371, 1218327968
OFFSET
1,1
COMMENTS
Column 3 of A252811
LINKS
FORMULA
Empirical: a(n) = a(n-1) +11*a(n-3) -11*a(n-4) -30*a(n-6) +30*a(n-7) -2*a(n-9) +2*a(n-10) +7*a(n-12) -7*a(n-13) -a(n-15) +a(n-16) for n>19
EXAMPLE
Some solutions for n=2
..0..1..2..0..3....0..1..2..3..1....0..1..2..3..1....0..1..2..3..4
..4..3..1..4..0....1..0..2..1..0....2..2..2..2..2....4..0..2..4..0
..2..0..3..2..4....2..2..2..2..2....1..3..2..1..4....2..2..2..2..2
..1..4..0..1..2....4..1..2..0..1....3..4..2..3..1....3..4..2..0..1
CROSSREFS
Sequence in context: A277765 A357775 A052479 * A252027 A241931 A166916
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 22 2014
STATUS
approved