A222272 - OEIS

%I #4 Feb 14 2013 05:29:48

%S 3,13,81,1042,15309,259827,4721919,86605540,1596666209,29636427761,

%T 549614164013,10257852048210,190742396582721,3570677543208821,

%U 66567622846173385,1248868982288193670,23339378621029149099

%N Number of nX4 0..3 arrays with exactly floor(nX4/2) elements unequal to at least one horizontal or vertical neighbor, with new values introduced in row major 0..3 order

%C Column 4 of A222275

%H R. H. Hardin, <a href="/A222272/b222272.txt">Table of n, a(n) for n = 1..49</a>

%e Some solutions for n=3

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Feb 14 2013