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 A186568 T(n,k)=Number of (n+2)X(k+2) 0..2 arrays with every 3X3 subblock commuting with each horizontal and vertical neighbor 3X3 subblock 10
 19683, 721, 721, 2917, 173, 2917, 6594, 401, 401, 6594, 12122, 1411, 1399, 1411, 12122, 20056, 2617, 3421, 3421, 2617, 20056, 29303, 3379, 4807, 8983, 4807, 3379, 29303, 35198, 4033, 5605, 11557, 11557, 5605, 4033, 35198, 53611, 4795, 6511, 12895 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Table starts .19683...721..2917..6594.12122.20056..29303..35198..53611..85029.121783.199305 ...721...173...401..1411..2617..3379...4033...4795...6361..10443..17153..26995 ..2917...401..1399..3421..4807..5605...6511...8029..11647..19237..31623..49805 ..6594..1411..3421..8983.11557.12895..14845..18415..25381..40279..63565.102591 .12122..2617..4807.11557.21007.23389..27391..33445..44263..68269.104335.154693 .20056..3379..5605.12895.23389.29935..36133..44887..60493..91519.137701.205879 .29303..4033..6511.14845.27391.36133..47719..60973..82447.122725.185863.278125 .35198..4795..8029.18415.33445.44887..60973..82783.112357.168727.255085.381007 .53611..6361.11647.25381.44263.60493..82447.112357.168391.250285.374335.562933 .85029.10443.19237.40279.68269.91519.122725.168727.250285.441199.644917.946087 LINKS R. H. Hardin, Table of n, a(n) for n = 1..1404 FORMULA Empirical, for all columns: a(n)=2*a(n-1)-a(n-2)+2*a(n-3)-4*a(n-4)+2*a(n-5)+2*a(n-6)-2*a(n-7) for n>18,10,11,12,13,14,15,16 respectively for k=1..8 EXAMPLE Some solutions for 5X4 ..0..0..1..0....0..0..0..1....0..0..0..1....0..0..0..0....1..0..0..0 ..2..0..0..1....0..0..0..0....0..0..0..1....0..0..0..0....0..0..0..0 ..0..2..0..0....0..0..0..0....0..0..0..1....1..0..0..0....0..0..0..0 ..0..0..2..0....1..0..0..0....0..0..0..1....2..1..0..0....0..0..0..0 ..0..0..0..2....0..0..0..2....0..0..0..1....1..2..1..0....0..1..0..0 CROSSREFS Sequence in context: A206133 A321825 A186559 * A186560 A046322 A224658 Adjacent sequences:  A186565 A186566 A186567 * A186569 A186570 A186571 KEYWORD nonn,tabl AUTHOR R. H. Hardin Feb 23 2011 STATUS approved

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Last modified December 3 15:58 EST 2021. Contains 349467 sequences. (Running on oeis4.)