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A252968
Number of (7+2)X(n+2) 0..4 arrays with every consecutive three elements in every row and diagonal having exactly two distinct values, and in every column and antidiagonal not having exactly two distinct values, and new values 0 upwards introduced in row major order
1
7637, 2279, 2999, 4275, 6091, 8767, 12573, 19192, 27929, 42791, 65583, 101848, 157361, 254327, 399081, 649951, 1052501, 1735205, 2832701, 4772867, 7869665, 13341100, 22324855, 38106121, 64052857, 110368012, 186366733, 322104251
OFFSET
1,1
COMMENTS
Row 7 of A252961
LINKS
FORMULA
Empirical: a(n) = 6*a(n-2) +6*a(n-3) -10*a(n-4) -36*a(n-5) -9*a(n-6) +60*a(n-7) +68*a(n-8) -6*a(n-9) -108*a(n-10) -48*a(n-11) +24*a(n-12) +48*a(n-13) +25*a(n-14) -24*a(n-15) +22*a(n-16) -30*a(n-17) +22*a(n-18) -12*a(n-19) +33*a(n-20) -12*a(n-21) -18*a(n-23) for n>25
EXAMPLE
Some solutions for n=2
..0..1..1..2....0..0..1..1....0..1..1..2....0..0..1..0....0..1..1..2
..3..0..0..1....2..2..0..0....3..3..4..4....2..0..0..1....3..0..0..4
..4..3..3..0....3..3..2..2....2..0..0..1....3..0..3..3....2..3..3..1
..1..4..4..3....1..1..3..3....1..1..3..3....0..0..2..0....4..2..2..0
..0..1..1..4....4..4..1..1....3..2..2..0....4..0..0..2....1..4..4..2
..2..0..0..1....0..0..4..4....4..4..1..1....3..0..3..3....3..1..1..4
..3..2..2..0....3..3..0..0....0..3..3..2....0..0..4..0....0..3..3..1
..4..3..3..2....2..2..3..3....2..2..4..4....2..0..0..4....4..0..0..3
..1..4..4..3....4..4..2..4....1..0..0..3....1..0..1..1....1..2..2..0
CROSSREFS
Sequence in context: A068245 A189551 A235907 * A252051 A038011 A205040
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 25 2014
STATUS
approved