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 A251839 Number of (n+2) X (2+2) 0..3 arrays with every 3 X 3 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 Cf. A251845. 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 January 28 04:30 EST 2022. Contains 350654 sequences. (Running on oeis4.)