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A207415 Number of n X 4 0..1 arrays avoiding 0 0 1 and 0 1 0 horizontally and 0 1 1 and 1 0 1 vertically.

%I A207415 #7 Apr 21 2021 11:06:41
%S A207415 9,81,241,742,2760,8465,24317,73405,214117,601411,1698702,4766632,
%T A207415 13156641,36175599,99198867,270109351,732494449,1982055330,5345239912,
%U A207415 14374634237,38587852393,103391960861,276535572481,738655032563
%N A207415 Number of n X 4 0..1 arrays avoiding 0 0 1 and 0 1 0 horizontally and 0 1 1 and 1 0 1 vertically.
%C A207415 Column 4 of A207419.
%H A207415 R. H. Hardin, <a href="/A207415/b207415.txt">Table of n, a(n) for n = 1..210</a>
%F A207415 Empirical: a(n) = 5*a(n-1) -8*a(n-2) +23*a(n-3) -74*a(n-4) +70*a(n-5) -116*a(n-6) +362*a(n-7) -122*a(n-8) +152*a(n-9) -916*a(n-10) -166*a(n-11) +26*a(n-12) +1638*a(n-13) +657*a(n-14) -225*a(n-15) -1890*a(n-16) -895*a(n-17) +372*a(n-18) +1268*a(n-19) +486*a(n-20) -190*a(n-21) -454*a(n-22) -122*a(n-23) +60*a(n-24) +60*a(n-25).
%e A207415 Some solutions for n=4
%e A207415 ..1..1..0..1....1..0..0..0....0..0..0..0....1..1..0..1....1..1..1..1
%e A207415 ..0..0..0..0....1..1..1..1....0..0..0..0....1..1..0..1....1..0..0..0
%e A207415 ..0..0..0..0....1..0..0..0....1..1..0..0....0..1..1..0....0..0..0..0
%e A207415 ..1..0..1..1....1..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0
%Y A207415 Cf. A207419.
%K A207415 nonn
%O A207415 1,1
%A A207415 _R. H. Hardin_ Feb 17 2012