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Number of (n+2)X(n+2) 0..1 arrays with every 3X3 subblock having three equal elements in a row horizontally, vertically, diagonally or antidiagonally exactly three ways, and new values 0..1 introduced in row major order
0

%I #7 May 04 2016 21:34:38

%S 40,46,22,32,48,74,116,184,294,472,760,1226,1980,3200,5174,8368,13536,

%T 21898,35428,57320,92742,150056,242792,392842

%N Number of (n+2)X(n+2) 0..1 arrays with every 3X3 subblock having three equal elements in a row horizontally, vertically, diagonally or antidiagonally exactly three ways, and new values 0..1 introduced in row major order

%C Diagonal of A204754

%H W. Kuszmaul, <a href="http://arxiv.org/abs/1509.08216">Fast Algorithms for Finding Pattern Avoiders and Counting Pattern Occurrences in Permutations</a>, arXiv preprint arXiv:1509.08216, 2015

%e Some solutions for n=6

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

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

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Jan 18 2012