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A251839 Number of (n+2)X(2+2) 0..3 arrays with every 3X3 subblock row and column sum nonprime and every diagonal and antidiagonal sum prime 1
981, 508, 828, 1229, 2672, 5438, 9647, 22610, 47398, 86279, 204832, 432320, 789967, 1882338, 3983708, 7285937, 17386988, 36844782, 67409449, 160977268, 341342946, 624601177, 1492090228, 3164874902, 5791630811, 13837769762, 29355806776 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 2 of A251845

LINKS

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

FORMULA

Empirical: a(n) = 17*a(n-3) -90*a(n-6) +191*a(n-9) -205*a(n-12) +128*a(n-15) -48*a(n-18) +8*a(n-21) for n>26

EXAMPLE

Some solutions for n=4

..0..1..0..0....1..1..2..1....0..1..0..3....0..3..1..0....3..1..0..0

..0..1..0..3....0..0..1..0....0..1..0..0....0..0..1..0....0..1..0..3

..1..2..1..1....0..3..1..0....1..2..1..1....1..1..2..1....1..2..1..1

..3..1..0..0....1..1..2..1....0..1..3..0....0..0..1..0....0..1..0..0

..0..1..0..0....3..0..1..0....3..1..0..0....0..0..1..3....0..1..0..0

..1..2..1..1....0..3..1..0....3..2..1..1....1..1..2..1....1..2..1..1

CROSSREFS

Sequence in context: A109120 A128483 A056937 * A122472 A252402 A087907

Adjacent sequences:  A251836 A251837 A251838 * A251840 A251841 A251842

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 09 2014

STATUS

approved

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Last modified September 25 22:49 EDT 2020. Contains 337346 sequences. (Running on oeis4.)