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A252413
Number of (6+2)X(n+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 2 3 4 6 or 7 and every 3X3 column and antidiagonal sum not equal to 2 3 4 6 or 7
1
964, 5061, 20998, 44456, 249530, 1068295, 2289969, 12895653, 55487440, 119202170, 674431408, 2912481205, 6264133843, 35589145875, 154113611916, 331758653516, 1891057365728, 8206533730107, 17678178284409, 101024088846291
OFFSET
1,1
COMMENTS
Row 6 of A252407
LINKS
FORMULA
Empirical: a(n) = 95*a(n-3) -2139*a(n-6) -7409*a(n-9) +194956*a(n-12) +60848*a(n-15) -7025702*a(n-18) +7788378*a(n-21) +119742541*a(n-24) -273713371*a(n-27) -671051999*a(n-30) +2708582795*a(n-33) -2329474380*a(n-36) -526768608*a(n-39) +1416261076*a(n-42) -328618104*a(n-45) -188072944*a(n-48) +71753184*a(n-51) +2455488*a(n-54) -2353536*a(n-57) +248832*a(n-60) for n>63
EXAMPLE
Some solutions for n=4
..2..0..2..2..3..2....2..2..3..2..2..0....1..3..3..1..3..3....2..3..2..2..3..2
..2..2..3..2..2..3....3..2..2..3..2..2....2..0..2..2..3..2....2..2..3..2..2..3
..1..3..3..1..3..0....3..1..3..3..1..3....2..2..3..2..2..0....1..3..0..1..3..3
..2..0..2..2..3..2....2..2..3..2..2..0....1..3..0..1..3..3....2..3..2..2..3..2
..2..2..3..2..2..3....3..2..2..3..2..2....2..3..2..2..0..2....2..2..3..2..2..3
..1..3..3..1..3..3....3..1..3..3..1..3....2..2..3..2..2..3....1..3..3..1..3..3
..2..3..2..2..0..2....2..2..3..2..2..3....1..0..3..1..3..3....2..3..2..2..3..2
..2..2..3..2..2..3....0..2..2..0..2..2....2..3..2..2..0..2....2..2..3..2..2..0
CROSSREFS
Sequence in context: A347884 A031709 A158413 * A267973 A267996 A093232
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 17 2014
STATUS
approved