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A207661 T(n,k)=Number of nXk 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 1 0 0 vertically.

%I A207661 #7 Jul 22 2025 20:38:57
%S A207661 2,4,4,6,16,6,10,36,36,9,16,100,84,81,14,26,256,292,198,196,22,42,676,
%T A207661 912,870,474,484,35,68,1764,2812,3358,2774,1140,1225,56,110,4624,8928,
%U A207661 12040,13902,9060,2748,3136,90,178,12100,28152,47320,55752,60762,30440
%N A207661 T(n,k)=Number of nXk 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 1 0 0 vertically.
%C A207661 Table starts
%C A207661 ..2....4....6.....10......16......26.......42.........68........110.........178
%C A207661 ..4...16...36....100.....256.....676.....1764.......4624......12100.......31684
%C A207661 ..6...36...84....292.....912....2812.....8928......28152......87972......277292
%C A207661 ..9...81..198....870....3358...12040....47320.....182192.....676396.....2611234
%C A207661 .14..196..474...2774...13902...55752...284272....1391724....6009486....29516206
%C A207661 .22..484.1140...9060...60762..264568..1806676...11731102...56370696...366295198
%C A207661 .35.1225.2748..30440..284108.1296732.12327618..111194040..568720390..5097396968
%C A207661 .56.3136.6630.103838.1384420.6454684.87753008.1144562438.5955572036.76412972266
%H A207661 R. H. Hardin, <a href="/A207661/b207661.txt">Table of n, a(n) for n = 1..420</a>
%e A207661 Some solutions for n=4 k=3
%e A207661 ..0..1..1....0..1..0....0..1..1....1..1..0....0..0..1....0..1..1....1..0..0
%e A207661 ..1..0..0....1..1..0....1..0..0....1..0..1....1..1..0....1..1..0....0..1..1
%e A207661 ..0..1..1....1..0..0....0..1..1....0..1..1....1..0..1....1..0..1....1..0..0
%e A207661 ..1..1..0....0..1..0....1..0..1....1..1..0....1..1..0....0..1..1....0..1..1
%Y A207661 Column 1 is A001611(n+2)
%Y A207661 Column 2 is A207436
%Y A207661 Row 1 is A006355(n+2)
%Y A207661 Row 2 is A206981
%Y A207661 Row 3 is A207341
%K A207661 nonn,tabl
%O A207661 1,1
%A A207661 _R. H. Hardin_ Feb 19 2012