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A252304 Number of (n+2) X (7+2) 0..3 arrays with every 3 X 3 subblock row and diagonal sum equal to 0 1 3 6 or 7 and every 3 X 3 column and antidiagonal sum not equal to 0 1 3 6 or 7. 1
12027, 7625, 8650, 11639, 22521, 34279, 48579, 109845, 172039, 240515, 630341, 1001223, 1372035, 4084741, 6541831, 8798211, 28880133, 46506247, 61723395, 215907589, 348800263, 459211011, 1666815237, 2697504007, 3535502595 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Column 7 of A252305.
LINKS
FORMULA
Empirical: a(n) = 15*a(n-3) -70*a(n-6) +120*a(n-9) -64*a(n-12) for n>24.
EXAMPLE
Some solutions for n=4
..0..0..0..0..3..3..0..3..3....3..1..2..0..1..2..3..1..2
..1..3..2..1..0..2..1..0..2....3..0..3..0..0..0..3..0..0
..1..2..0..1..2..0..1..2..3....2..1..3..2..1..0..2..1..0
..0..3..3..0..3..3..0..0..0....0..1..2..3..1..2..3..1..2
..1..0..2..1..0..2..1..3..2....0..0..0..3..0..0..3..0..3
..1..2..0..1..2..3..1..2..0....2..1..0..2..1..0..2..1..0
CROSSREFS
Cf. A252305.
Sequence in context: A235308 A064966 A292815 * A251680 A247688 A236726
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 16 2014
STATUS
approved

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Last modified March 28 18:04 EDT 2024. Contains 371254 sequences. (Running on oeis4.)