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A252190
Number of (n+2)X(6+2) 0..3 arrays with every 3X3 subblock row and column sum equal to 0 1 3 6 or 7 and every 3X3 diagonal and antidiagonal sum not equal to 0 1 3 6 or 7
1
7973, 9508, 13737, 21417, 37035, 57629, 87230, 150297, 239980, 380896, 661172, 1077056, 1764648, 3158368, 5312912, 9015496, 16782224, 29334608, 51772488, 100395856, 182091344, 332883016, 667871312, 1246565456, 2338093128
OFFSET
1,1
COMMENTS
Column 6 of A252192
LINKS
FORMULA
Empirical: a(n) = 15*a(n-3) -70*a(n-6) +120*a(n-9) -64*a(n-12) for n>21
EXAMPLE
Some solutions for n=4
..2..3..1..2..0..1..2..3....2..2..3..1..2..3..1..2....0..1..2..3..1..2..0..1
..1..1..1..1..1..1..1..1....3..0..0..0..0..0..0..0....0..3..3..0..0..3..0..3
..3..2..1..0..2..1..3..2....2..1..3..2..1..3..2..1....3..2..1..0..2..1..0..2
..2..0..1..2..3..1..2..0....1..2..0..1..2..3..1..2....0..1..2..0..1..2..3..1
..1..1..1..1..1..1..1..1....3..0..0..3..0..0..0..0....3..3..0..0..3..3..0..0
..3..2..1..3..2..1..0..0....2..1..3..2..1..3..2..1....0..2..1..3..2..1..0..0
CROSSREFS
Sequence in context: A254138 A157660 A236786 * A233730 A175507 A126893
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 15 2014
STATUS
approved