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A303469 T(n,k)=Number of nXk 0..1 arrays with every element equal to 0, 1, 2, 3, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero. 12

%I #4 Apr 24 2018 10:43:32

%S 1,2,2,4,8,4,8,29,32,8,16,105,170,128,16,32,384,948,1033,512,32,64,

%T 1405,5237,9110,6369,2048,64,128,5135,29009,79377,89371,39098,8192,

%U 128,256,18766,160590,692636,1243692,872026,240109,32768,256,512,68589,888993

%N T(n,k)=Number of nXk 0..1 arrays with every element equal to 0, 1, 2, 3, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

%C Table starts

%C ...1......2.......4.........8..........16............32..............64

%C ...2......8......29.......105.........384..........1405............5135

%C ...4.....32.....170.......948........5237.........29009..........160590

%C ...8....128....1033......9110.......79377........692636.........6051850

%C ..16....512....6369.....89371.....1243692......17247543.......239939422

%C ..32...2048...39098....872026....19374638.....427097893......9459086839

%C ..64...8192..240109...8511918...302023677...10589284528....373571747330

%C .128..32768.1476141..83188773..4716032889..263136262937..14793218857797

%C .256.131072.9071642.812770434.73624207904.6538180319944.585806882371397

%H R. H. Hardin, <a href="/A303469/b303469.txt">Table of n, a(n) for n = 1..180</a>

%F Empirical for column k:

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

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

%F k=3: a(n) = 7*a(n-1) -5*a(n-2) +20*a(n-3) -144*a(n-4) +72*a(n-5) for n>6

%F k=4: [order 20] for n>21

%F k=5: [order 93] for n>94

%F Empirical for row n:

%F n=1: a(n) = 2*a(n-1)

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

%F n=3: [order 14] for n>15

%F n=4: [order 49] for n>50

%e Some solutions for n=5 k=4

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

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

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

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

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

%Y Column 1 is A000079(n-1).

%Y Column 2 is A004171(n-1).

%Y Row 1 is A000079(n-1).

%Y Row 2 is A302266.

%K nonn,tabl

%O 1,2

%A _R. H. Hardin_, Apr 24 2018

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Last modified April 24 00:30 EDT 2024. Contains 371917 sequences. (Running on oeis4.)