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A240519 T(n,k)=Number of nXk 0..1 arrays with no element equal to exactly two horizontal and vertical neighbors, with new values 0..1 introduced in row major order 8

%I

%S 1,2,2,3,3,3,5,6,6,5,8,10,10,10,8,13,21,28,28,21,13,21,42,73,99,73,42,

%T 21,34,86,196,326,326,196,86,34,55,179,515,1080,1376,1080,515,179,55,

%U 89,370,1376,3765,6205,6205,3765,1376,370,89,144,770,3686,13282,28942,37624

%N T(n,k)=Number of nXk 0..1 arrays with no element equal to exactly two horizontal and vertical neighbors, with new values 0..1 introduced in row major order

%C Table starts

%C ..1...2....3......5.......8.......13.........21..........34...........55

%C ..2...3....6.....10......21.......42.........86.........179..........370

%C ..3...6...10.....28......73......196........515........1376.........3686

%C ..5..10...28.....99.....326.....1080.......3765.......13282........46928

%C ..8..21...73....326....1376.....6205......28942......135093.......636475

%C .13..42..196...1080....6205....37624.....231665.....1440880......9082172

%C .21..86..515...3765...28942...231665....1906245....16000486....135790448

%C .34.179.1376..13282..135093..1440880...16000486...180760099...2056580724

%C .55.370.3686..46928..636475..9082172..135790448..2056580724..31517059634

%C .89.770.9914.166611.3024792.57688194.1158315893.23588995330.488025204070

%H R. H. Hardin, <a href="/A240519/b240519.txt">Table of n, a(n) for n = 1..220</a>

%F Empirical for column k:

%F k=1: a(n) = a(n-1) +a(n-2)

%F k=2: a(n) = 2*a(n-1) +a(n-2) -a(n-3) -2*a(n-4) +a(n-5)

%F k=3: [order 20]

%F k=4: [order 48]

%e Some solutions for n=4 k=4

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

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

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

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

%Y Column 1 is A000045(n+1)

%K nonn,tabl

%O 1,2

%A _R. H. Hardin_, Apr 06 2014

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Last modified March 5 14:57 EST 2021. Contains 341823 sequences. (Running on oeis4.)