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A222290 T(n,k)=Number of nXk 0..1 arrays with exactly floor(nXk/2) elements unequal to at least one horizontal or vertical neighbor, with new values introduced in row major 0..1 order.

%I A222290 #6 Jul 23 2025 02:29:10
%S A222290 1,0,0,0,0,0,3,4,4,3,4,11,4,11,4,4,8,35,35,8,4,5,44,83,208,83,44,5,20,
%T A222290 144,532,1125,1125,532,144,20,27,352,1427,6619,6582,6619,1427,352,27,
%U A222290 48,692,8540,40321,89852,89852,40321,8540,692,48,63,2488,23798,250681
%N A222290 T(n,k)=Number of nXk 0..1 arrays with exactly floor(nXk/2) elements unequal to at least one horizontal or vertical neighbor, with new values introduced in row major 0..1 order.
%C A222290 Table starts
%C A222290 ...1.....0.......0.........3...........4..............4..............5
%C A222290 ...0.....0.......4........11...........8.............44............144
%C A222290 ...0.....4.......4........35..........83............532...........1427
%C A222290 ...3....11......35.......208........1125...........6619..........40321
%C A222290 ...4.....8......83......1125........6582..........89852.........564838
%C A222290 ...4....44.....532......6619.......89852........1249354.......17801910
%C A222290 ...5...144....1427.....40321......564838.......17801910......262048125
%C A222290 ..20...352....8540....250681.....7879795......256986006.....8550246097
%C A222290 ..27...692...23798...1569385....50958999.....3744123550...129184703815
%C A222290 ..48..2488..143594...9860229...723447048....55066210090..4294346570524
%C A222290 ..63..6476..405187..62350467..4750196831...815041154350.66002018148195
%C A222290 .175.17095.2455279.395971584.67994171066.12128319606229
%H A222290 R. H. Hardin, <a href="/A222290/b222290.txt">Table of n, a(n) for n = 1..161</a>
%e A222290 Some solutions for n=4 k=4
%e A222290 ..0..0..0..1....0..0..0..0....0..0..1..1....0..1..1..1....0..0..0..1
%e A222290 ..0..0..0..0....1..1..0..0....0..0..1..1....1..1..1..1....0..0..1..1
%e A222290 ..1..0..0..0....1..1..1..1....0..0..0..1....1..1..1..0....0..0..1..1
%e A222290 ..1..0..0..0....1..1..1..1....0..0..0..1....1..1..0..0....0..0..1..1
%K A222290 nonn,tabl
%O A222290 1,7
%A A222290 _R. H. Hardin_ Feb 14 2013