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A252724
Number of (5+2) X (n+2) 0..3 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
111, 102, 119, 135, 147, 191, 211, 251, 323, 375, 447, 599, 691, 851, 1139, 1335, 1647, 2231, 2611, 3251, 4403, 5175, 6447, 8759, 10291, 12851, 17459, 20535, 25647, 34871, 41011, 51251, 69683, 81975, 102447, 139319, 163891, 204851, 278579, 327735
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = -a(n-1) + 3*a(n-3) + 3*a(n-4) - 2*a(n-6) - 2*a(n-7) for n>9.
Empirical g.f.: x*(111 + 213*x + 221*x^2 - 79*x^3 - 357*x^4 - 325*x^5 - 138*x^6 + 42*x^7 + 2*x^8) / ((1 - x)*(1 + x)*(1 + x + x^2)*(1 - 2*x^3)). - Colin Barker, Dec 06 2018
EXAMPLE
Some solutions for n=4:
..0..1..0..0..1..0....0..1..0..0..1..0....0..1..0..0..2..0....0..1..0..0..2..0
..2..2..0..2..2..0....0..0..1..0..0..2....3..3..0..3..3..0....3..3..0..3..3..0
..1..0..0..1..0..0....0..3..3..0..3..3....2..0..0..1..0..0....1..0..0..1..0..0
..0..1..0..0..1..0....0..1..0..0..1..0....0..2..0..0..1..0....0..1..0..0..1..0
..2..2..0..2..2..0....0..0..1..0..0..1....3..3..0..3..3..0....3..3..0..3..3..0
..1..0..0..1..0..0....0..2..2..0..2..2....1..0..0..2..0..0....1..0..0..1..0..0
..0..1..0..0..1..0....0..1..0..0..1..0....0..1..0..0..2..0....0..2..0..0..1..0
CROSSREFS
Row 5 of A252719.
Sequence in context: A072807 A282976 A284083 * A073502 A066335 A107844
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 20 2014
STATUS
approved