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%I #5 Mar 31 2012 12:37:01
%S 7580,16792,35690,71465,174154,412860,901622,2013562,4631014,10741246,
%T 24250558,54895662,124980670,286185464,650745046,1479976784,
%U 3367789342,7679928184,17482919110,39803180062,90607144520,206396554876
%N Number of (n+2)X7 0..1 arrays with every 3X3 subblock having three equal elements in a row horizontally, vertically, diagonally or antidiagonally exactly one way, and new values 0..1 introduced in row major order
%C Column 5 of A204361
%H R. H. Hardin, <a href="/A204358/b204358.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 3*a(n-1) -4*a(n-2) +5*a(n-3) +9*a(n-4) -31*a(n-5) +49*a(n-6) -59*a(n-7) +15*a(n-8) +54*a(n-9) -102*a(n-10) +110*a(n-11) -52*a(n-12) -25*a(n-13) +74*a(n-14) -77*a(n-15) +38*a(n-16) +2*a(n-17) -18*a(n-18) +17*a(n-19) -8*a(n-20) +a(n-21) for n>30
%e Some solutions for n=3
%e ..0..1..1..1..0..0..0....0..0..0..1..1..0..0....0..0..0..1..1..1..1
%e ..0..1..0..1..0..1..0....0..1..0..1..0..0..1....0..1..0..1..0..0..1
%e ..1..0..1..0..1..0..1....1..0..1..0..0..1..0....1..0..1..0..0..1..0
%e ..0..0..1..1..1..0..0....1..0..0..0..1..1..0....1..0..0..1..1..1..0
%e ..1..0..0..1..0..0..1....1..1..0..1..1..0..0....1..1..0..0..1..0..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Jan 14 2012