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A251651
Number of (n+2)X(7+2) 0..3 arrays with no row, column, diagonal or antidiagonal in any 3X3 subblock summing to 0 2 4 5 7 or 9
1
6978, 49956, 163318, 610082, 5248890, 17185778, 63447690, 562400186, 1826236602, 6707952986, 60713749434, 196015117610, 717238558554, 6591100286714, 21191371865802, 77327675043578, 718376458646010, 2302904073545738
OFFSET
1,1
COMMENTS
Column 7 of A251652
LINKS
FORMULA
Empirical: a(n) = 4*a(n-1) +3*a(n-2) +101*a(n-3) -438*a(n-4) -329*a(n-5) +990*a(n-6) -220*a(n-7) -110*a(n-8) for n>13
EXAMPLE
Some solutions for n=3
..1..0..2..1..0..2..1..3..2....3..2..1..0..2..1..0..2..1
..1..3..2..1..3..2..1..0..2....0..2..1..0..2..1..3..2..1
..1..3..2..1..3..2..1..3..2....0..2..1..3..2..1..0..2..1
..1..0..2..1..0..2..1..3..2....3..2..1..0..2..1..0..2..1
..1..0..2..1..3..2..1..0..2....3..2..1..3..2..1..3..2..1
CROSSREFS
Sequence in context: A050225 A305718 A237237 * A050673 A050663 A114615
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 06 2014
STATUS
approved