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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

R. H. Hardin, Table of n, a(n) for n = 1..210

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

Adjacent sequences:  A251837 A251838 A251839 * A251841 A251842 A251843

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 09 2014

STATUS

approved

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Last modified January 18 18:56 EST 2018. Contains 297864 sequences.