A222511 - OEIS

%I #4 Feb 23 2013 17:10:35

%S 0,4,4,15,35,170,441,2192,5416,26660,66209,328121,816736,4074688,

%T 10172187,51053330,127212627,643151980,1598614930,8135779154,

%U 20183768037,103256080822,255983883834,1314494576457,3259213240495,16780895442470

%N Number of 3Xn 0..1 arrays with exactly floor(3Xn/2) elements unequal to at least one horizontal, diagonal or antidiagonal neighbor, with new values introduced in row major 0..1 order

%C Row 3 of A222509

%H R. H. Hardin, <a href="/A222511/b222511.txt">Table of n, a(n) for n = 1..77</a>

%e All solutions for n=3

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

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

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

%K nonn

%O 1,2

%A _R. H. Hardin_ Feb 23 2013