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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

%I

%S 641,828,1803,2890,8582,21748,40492,128431,339592,639794,2087597,

%T 5632271,10609658,35199882,96069006,180868454,605781397,1663988392,

%U 3131743910,10543905961,29063878897,54690404276,184648426284,509929622436

%N 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

%C Column 3 of A251845

%H R. H. Hardin, <a href="/A251840/b251840.txt">Table of n, a(n) for n = 1..210</a>

%F 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

%e Some solutions for n=4

%e ..0..0..1..0..0....3..0..1..0..3....1..1..2..1..1....0..0..1..3..0

%e ..1..1..2..1..1....1..1..2..1..1....3..0..1..0..0....1..1..2..1..1

%e ..0..0..1..0..0....0..3..1..0..0....0..0..1..0..3....0..0..1..0..0

%e ..3..0..1..3..0....0..0..1..0..3....1..1..2..1..1....0..3..1..0..0

%e ..1..1..2..1..1....1..1..2..1..1....0..0..1..3..0....1..1..2..1..1

%e ..0..0..1..0..3....3..0..1..0..0....3..0..1..0..0....0..0..1..0..3

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 09 2014

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Last modified September 27 22:36 EDT 2020. Contains 337388 sequences. (Running on oeis4.)