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 A188861 Number of n X 4 binary arrays without the pattern 0 1 diagonally, vertically or antidiagonally. 2

%I

%S 16,41,68,95,122,149,176,203,230,257,284,311,338,365,392,419,446,473,

%T 500,527,554,581,608,635,662,689,716,743,770,797,824,851,878,905,932,

%U 959,986,1013,1040,1067,1094,1121,1148,1175,1202,1229,1256,1283,1310,1337,1364

%N Number of n X 4 binary arrays without the pattern 0 1 diagonally, vertically or antidiagonally.

%C Column 4 of A188866.

%H R. H. Hardin, <a href="/A188861/b188861.txt">Table of n, a(n) for n = 1..200</a>

%F Empirical: a(n) = 27*n - 13 for n>1.

%F Conjectures from _Colin Barker_, Feb 28 2018: (Start)

%F G.f.: x*(16 + 9*x + 2*x^2) / (1 - x)^2.

%F a(n) = 2*a(n-1) - a(n-2) for n>3.

%F (End)

%e Some solutions for 3 X 4:

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

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

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

%t Join[{16}, Range[41, 7000, 27]] (* _Vladimir Joseph Stephan Orlovsky_, Jul 13 2011 *)

%Y Cf. A188866.

%K nonn

%O 1,1

%A _R. H. Hardin_, Apr 12 2011

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Last modified March 19 20:41 EDT 2018. Contains 300868 sequences. (Running on oeis4.)