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A252241
Number of (n+2)X(6+2) 0..3 arrays with every 3X3 subblock row and column sum not equal to 1 3 4 6 or 7 and every 3X3 diagonal and antidiagonal sum equal to 1 3 4 6 or 7
1
34364, 932024, 22430004, 84935088, 2778727776, 78534150416, 267361717440, 9906342078848, 303070072292928, 959873651073792, 38221223204832768, 1212189579390626048, 3685070395096108032, 152413070389286672384
OFFSET
1,1
COMMENTS
Column 6 of A252243
LINKS
FORMULA
Empirical: a(n) = 7180*a(n-3) -14766112*a(n-6) +8766324736*a(n-9) -103548977152*a(n-12) +274877906944*a(n-15) for n>16
EXAMPLE
Some solutions for n=1
..2..3..3..2..0..0..2..3....0..2..0..3..2..3..3..2....0..0..2..3..3..2..3..3
..2..0..0..2..3..0..2..0....1..3..1..1..0..1..1..0....2..2..1..2..2..1..2..2
..1..2..2..1..2..2..1..2....1..3..1..1..0..1..1..3....3..3..2..0..0..2..0..0
CROSSREFS
Sequence in context: A204411 A238927 A236796 * A233872 A055001 A164556
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 15 2014
STATUS
approved