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Number of (n+2)X(2+2) 0..4 arrays with every consecutive three elements in every row and diagonal having exactly two distinct values, and in every column and antidiagonal not having exactly two distinct values, and new values 0 upwards introduced in row major order
1

%I #4 Dec 25 2014 07:28:17

%S 119,120,185,337,596,1186,2279,4165,8552,16744,31079,64381,127298,

%T 237724,494963,983227,1846154,3851596,7687829,14482087,30290270,

%U 60671074,114655493,240248527,483021992,914633350,1921066049,3874689085

%N Number of (n+2)X(2+2) 0..4 arrays with every consecutive three elements in every row and diagonal having exactly two distinct values, and in every column and antidiagonal not having exactly two distinct values, and new values 0 upwards introduced in row major order

%C Column 2 of A252961

%H R. H. Hardin, <a href="/A252955/b252955.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 5*a(n-1) -6*a(n-2) +8*a(n-3) -55*a(n-4) +75*a(n-5) +71*a(n-6) -85*a(n-7) -42*a(n-8) -600*a(n-9) +1575*a(n-10) -1323*a(n-11) +378*a(n-12) for n>14

%e Some solutions for n=2

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

%e ..2..2..0..0....1..0..1..0....3..3..4..4....3..0..0..4....3..0..0..4

%e ..3..3..2..2....3..3..1..3....4..0..0..1....4..3..3..1....2..3..3..1

%e ..4..4..3..4....2..2..1..1....1..1..3..3....2..1..1..3....1..2..2..0

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 25 2014