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Equals one maps: number of nX4 binary arrays indicating the locations of corresponding elements equal to exactly one of their horizontal, vertical and antidiagonal neighbors in a random 0..2 nX4 array
1

%I #4 Dec 22 2012 03:41:22

%S 8,168,3466,62400,1037774,16734366,268264812,4294285044,68716748256,

%T 1099500713960,17592142389240,281474802089984,4503598928887808,

%U 72057591243997184,1152921493431123968,18446744029006659584

%N Equals one maps: number of nX4 binary arrays indicating the locations of corresponding elements equal to exactly one of their horizontal, vertical and antidiagonal neighbors in a random 0..2 nX4 array

%C Column 4 of A220810

%H R. H. Hardin, <a href="/A220808/b220808.txt">Table of n, a(n) for n = 1..33</a>

%F Empirical: a(n) = 20*a(n-1) -64*a(n-2) for n>13

%e Some solutions for n=3

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Dec 22 2012