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A252386 Number of (2+2)X(n+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 0 3 5 6 or 7 and every 3X3 column and antidiagonal sum not equal to 0 3 5 6 or 7 1
540, 555, 647, 771, 1067, 1496, 1928, 2662, 3856, 5074, 7024, 10213, 13505, 18776, 27325, 36221, 50467, 73399, 97476, 135968, 197447, 262661, 366593, 531297, 707931, 988319, 1429275, 1907450, 2663225, 3843093, 5136589, 7172051, 10327393 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Row 2 of A252384
LINKS
FORMULA
Empirical: a(n) = 9*a(n-3) -32*a(n-6) +58*a(n-9) -58*a(n-12) +32*a(n-15) -9*a(n-18) +a(n-21) for n>30
EXAMPLE
Some solutions for n=4
..1..0..2..1..0..2....0..2..3..0..3..3....2..0..3..0..0..3....3..2..1..3..2..1
..0..0..0..0..0..0....1..3..1..1..3..1....1..0..2..1..0..2....2..0..3..0..0..3
..0..1..2..0..1..2....3..3..0..3..3..0....1..2..3..1..2..3....3..2..0..1..2..0
..1..0..2..1..3..2....0..3..3..0..2..1....0..0..3..0..0..3....3..2..1..3..2..1
CROSSREFS
Sequence in context: A239347 A118630 A184546 * A289221 A345390 A261290
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 17 2014
STATUS
approved

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Last modified June 18 20:38 EDT 2024. Contains 373487 sequences. (Running on oeis4.)