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A283386 T(n,k)=Number of nXk 0..1 arrays with no 1 equal to more than two of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly two elements. 7

%I

%S 0,0,0,0,1,0,0,3,3,0,0,19,60,19,0,0,91,532,532,91,0,0,399,4420,8087,

%T 4420,399,0,0,1734,34531,116624,116624,34531,1734,0,0,7257,257416,

%U 1592250,2993934,1592250,257416,7257,0,0,29754,1862717,20788531,71707838

%N T(n,k)=Number of nXk 0..1 arrays with no 1 equal to more than two of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly two elements.

%C Table starts

%C .0.....0........0..........0............0...............0.................0

%C .0.....1........3.........19...........91.............399..............1734

%C .0.....3.......60........532.........4420...........34531............257416

%C .0....19......532.......8087.......116624.........1592250..........20788531

%C .0....91.....4420.....116624......2993934........71707838........1644385909

%C .0...399....34531....1592250.....71707838......3007934404......120672330232

%C .0..1734...257416...20788531...1644385909....120672330232.....8473366210380

%C .0..7257..1862717..264040297..36631580212...4702791428260...577497122717510

%C .0.29754.13180270.3282238215.797807876394.179057922328623.38429377558548084

%H R. H. Hardin, <a href="/A283386/b283386.txt">Table of n, a(n) for n = 1..180</a>

%F Empirical for column k:

%F k=1: a(n) = a(n-1)

%F k=2: [order 24]

%F k=3: [order 32]

%F k=4: [order 57] for n>58

%e Some solutions for n=4 k=4

%e ..1..1..1..0. .1..0..1..1. .0..0..1..0. .1..1..1..0. .0..0..0..1

%e ..0..0..1..0. .1..0..1..1. .1..1..0..0. .1..0..0..1. .1..0..1..0

%e ..0..0..1..0. .0..0..0..0. .1..0..1..0. .0..0..1..1. .1..0..1..1

%e ..0..1..1..1. .0..1..0..1. .1..1..0..0. .1..0..0..1. .0..1..1..0

%K nonn,tabl

%O 1,8

%A _R. H. Hardin_, Mar 06 2017

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Last modified January 24 13:11 EST 2022. Contains 350538 sequences. (Running on oeis4.)