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A252688 Number of (n+2)X(1+2) 0..3 arrays with every consecutive three elements in every row and column having exactly two distinct values, and in every diagonal and antidiagonal not having exactly two distinct values, and new values 0 upwards introduced in row major order 1

%I

%S 46,96,148,394,707,1982,3703,10772,20437,60042,115343,338174,656519,

%T 1913418,3749109,10848316,21436803,61563668,122626571,349539732,

%U 701532497,1985146994,4013145959,11276488886,22954622815,64065149914

%N Number of (n+2)X(1+2) 0..3 arrays with every consecutive three elements in every row and column having exactly two distinct values, and in every diagonal and antidiagonal not having exactly two distinct values, and new values 0 upwards introduced in row major order

%C Column 1 of A252695

%H R. H. Hardin, <a href="/A252688/b252688.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 2*a(n-1) +9*a(n-2) -15*a(n-3) -30*a(n-4) +21*a(n-5) +80*a(n-6) +18*a(n-7) -132*a(n-8) -76*a(n-9) +88*a(n-10) +108*a(n-11) -32*a(n-12) -40*a(n-13) for n>14

%e Some solutions for n=4

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 20 2014

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Last modified September 29 22:48 EDT 2022. Contains 357092 sequences. (Running on oeis4.)