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A208069 T(n,k)=Number of nXk 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 0 1 1 vertically.

%I A208069 #7 Jul 22 2025 21:08:48
%S A208069 2,4,4,6,16,6,10,36,36,9,16,100,72,81,12,26,256,240,144,144,16,42,676,
%T A208069 704,576,216,256,20,68,1764,2080,1936,1008,324,400,25,110,4624,6216,
%U A208069 6400,3696,1764,432,625,30,178,12100,18496,21904,12960,7056,2688,576,900,36
%N A208069 T(n,k)=Number of nXk 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 0 1 1 vertically.
%C A208069 Table starts
%C A208069 ..2...4...6...10....16....26.....42......68.....110......178.......288
%C A208069 ..4..16..36..100...256...676...1764....4624...12100....31684.....82944
%C A208069 ..6..36..72..240...704..2080...6216...18496...55000...163760....487296
%C A208069 ..9..81.144..576..1936..6400..21904...73984..250000...846400...2862864
%C A208069 .12.144.216.1008..3696.12960..48840..179520..657000..2423280...8913456
%C A208069 .16.256.324.1764..7056.26244.108900..435600.1726596..6937956..27751824
%C A208069 .20.400.432.2688.11424.44064.198000..844800.3542544.15213984..64859616
%C A208069 .25.625.576.4096.18496.73984.360000.1638400.7268416.33362176.151585344
%H A208069 R. H. Hardin, <a href="/A208069/b208069.txt">Table of n, a(n) for n = 1..766</a>
%e A208069 Some solutions for n=4 k=3
%e A208069 ..0..0..1....0..1..0....1..1..0....1..1..0....0..1..0....1..1..0....1..0..0
%e A208069 ..0..1..1....1..0..1....1..0..1....1..1..0....0..0..1....1..1..0....0..0..1
%e A208069 ..0..0..1....0..1..0....1..0..0....1..1..0....0..1..0....1..0..0....1..0..0
%e A208069 ..0..1..0....1..0..0....0..0..1....1..1..0....0..0..1....1..1..0....0..0..1
%Y A208069 Column 1 is A002620(n+2)
%Y A208069 Column 2 is A030179(n+2)
%Y A208069 Row 1 is A006355(n+2)
%Y A208069 Row 2 is A206981
%Y A208069 Row 3 is A207840
%Y A208069 Row 4 is A207924
%K A208069 nonn,tabl
%O A208069 1,1
%A A208069 _R. H. Hardin_ Feb 23 2012