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%I #5 Dec 21 2014 12:05:23
%S 234,1028,4687,22295,105956,507049,2429173,11652188,55960799,
%T 268783174,1291581364,6207376902,29836567197,143422264585,
%U 689472936242,3314565767875,15934867914351,76608704638459,368308600684650
%N Number of (n+2)X(1+2) 0..3 arrays with every consecutive three elements in every row, column and nw-se diagonal having exactly two distinct values, and new values 0 upwards introduced in row major order
%C Column 1 of A252777
%H R. H. Hardin, <a href="/A252771/b252771.txt">Table of n, a(n) for n = 1..210</a>
%H R. H. Hardin, <a href="/A252771/a252771.txt">Empirical recurrence of order 63</a>
%F Empirical recurrence of order 63 (see link above)
%e Some solutions for n=4
%e ..0..0..1....0..0..1....0..0..1....0..1..1....0..1..1....0..0..1....0..1..1
%e ..2..1..2....1..2..2....1..2..2....1..2..1....1..2..1....1..0..1....2..1..1
%e ..2..1..1....0..0..2....0..0..2....1..1..0....0..2..0....1..2..2....0..2..0
%e ..1..3..1....0..2..0....1..2..1....0..2..0....0..1..1....0..2..2....0..1..1
%e ..1..3..3....1..2..2....1..2..2....0..2..2....3..1..1....1..0..1....2..2..1
%e ..3..2..3....1..1..2....0..0..2....2..0..0....3..3..0....0..2..2....0..1..0
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 21 2014