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A251840 Number of (n+2)X(3+2) 0..3 arrays with every 3X3 subblock row and column sum nonprime and every diagonal and antidiagonal sum prime 1
641, 828, 1803, 2890, 8582, 21748, 40492, 128431, 339592, 639794, 2087597, 5632271, 10609658, 35199882, 96069006, 180868454, 605781397, 1663988392, 3131743910, 10543905961, 29063878897, 54690404276, 184648426284, 509929622436 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Column 3 of A251845
LINKS
FORMULA
Empirical: a(n) = 32*a(n-3) -310*a(n-6) +1096*a(n-9) -1790*a(n-12) +1558*a(n-15) -803*a(n-18) +238*a(n-21) -20*a(n-24) for n>33
EXAMPLE
Some solutions for n=4
..0..0..1..0..0....3..0..1..0..3....1..1..2..1..1....0..0..1..3..0
..1..1..2..1..1....1..1..2..1..1....3..0..1..0..0....1..1..2..1..1
..0..0..1..0..0....0..3..1..0..0....0..0..1..0..3....0..0..1..0..0
..3..0..1..3..0....0..0..1..0..3....1..1..2..1..1....0..3..1..0..0
..1..1..2..1..1....1..1..2..1..1....0..0..1..3..0....1..1..2..1..1
..0..0..1..0..3....3..0..1..0..0....3..0..1..0..0....0..0..1..0..3
CROSSREFS
Sequence in context: A256777 A252425 A160203 * A252433 A252434 A105130
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 09 2014
STATUS
approved

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Last modified February 25 17:53 EST 2024. Contains 370332 sequences. (Running on oeis4.)