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A252421 Number of (n+2)X(6+2) 0..3 arrays with every 3X3 subblock row and column sum not equal to 0 2 5 6 or 7 and every 3X3 diagonal and antidiagonal sum equal to 0 2 5 6 or 7 1
3719, 7186, 30724, 62288, 365974, 1757580, 3582225, 21882869, 107926383, 220463165, 1375056342, 6880842955, 14073466867, 88795680194, 447871169161, 916696939171, 5820110209906, 29480626550553, 60364093961967 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Column 6 of A252423
LINKS
FORMULA
Empirical: a(n) = 135*a(n-3) -6200*a(n-6) +129658*a(n-9) -1479172*a(n-12) +10122008*a(n-15) -43818900*a(n-18) +123860492*a(n-21) -233367460*a(n-24) +297742037*a(n-27) -261058827*a(n-30) +159867108*a(n-33) -69122310*a(n-36) +20695032*a(n-39) -3955984*a(n-42) +409280*a(n-45) -16896*a(n-48) for n>56
EXAMPLE
Some solutions for n=4
..0..3..1..0..0..1..0..0....1..1..2..1..1..2..1..1....1..1..2..1..1..2..1..1
..0..0..1..3..0..1..0..0....3..0..1..0..0..1..3..0....3..0..1..0..0..1..0..3
..1..1..2..1..1..2..1..1....0..0..1..0..3..1..0..0....0..0..1..0..0..1..0..0
..0..0..1..0..0..1..0..0....1..1..2..1..1..2..1..1....1..1..2..1..1..2..1..1
..3..0..1..0..0..1..3..0....3..0..1..0..0..1..0..3....0..0..1..0..0..1..0..0
..1..1..2..1..1..2..1..1....0..0..1..0..0..1..0..0....3..0..1..3..0..1..0..0
CROSSREFS
Sequence in context: A252161 A180396 A158917 * A296908 A237736 A289512
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 17 2014
STATUS
approved

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Last modified July 11 00:26 EDT 2024. Contains 374215 sequences. (Running on oeis4.)