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A281605 T(n,k)=Number of nXk 0..2 arrays with no element equal to more than one of its horizontal, diagonal or antidiagonal neighbors and with new values introduced in order 0 sequentially upwards. 11

%I #4 Jan 25 2017 10:40:46

%S 1,2,2,4,9,5,11,29,50,14,30,110,209,285,41,82,442,1283,1623,1617,122,

%T 224,1708,8180,16198,12413,9188,365,612,6596,49572,167545,203276,

%U 95623,52193,1094,1672,25624,302304,1626073,3401430,2563481,736757,296511,3281,4568

%N T(n,k)=Number of nXk 0..2 arrays with no element equal to more than one of its horizontal, diagonal or antidiagonal neighbors and with new values introduced in order 0 sequentially upwards.

%C Table starts

%C ....1.......2.........4..........11.............30.............82

%C ....2.......9........29.........110............442...........1708

%C ....5......50.......209........1283...........8180..........49572

%C ...14.....285......1623.......16198.........167545........1626073

%C ...41....1617.....12413......203276........3401430.......52899445

%C ..122....9188.....95623.....2563481.......69506779.....1732267694

%C ..365...52193....736757....32354824.....1421127262....56764280423

%C .1094..296511...5678559...408458506....29066686772..1860912910152

%C .3281.1684466..43771933..5156857179...594539026170.61012156448915

%C .9842.9569425.337417047.65107404580.12161158312943

%H R. H. Hardin, <a href="/A281605/b281605.txt">Table of n, a(n) for n = 1..112</a>

%F Empirical for column k:

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

%F k=2: a(n) = 6*a(n-1) -11*a(n-3) +4*a(n-4) for n>5

%F k=3: a(n) = 7*a(n-1) +10*a(n-2) -26*a(n-3) -64*a(n-4) -40*a(n-5) for n>6

%F k=4: [order 16] for n>18

%F k=5: [order 40] for n>42

%F Empirical for row n:

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

%F n=2: a(n) = 4*a(n-1) -2*a(n-2) +8*a(n-3) -8*a(n-4) for n>5

%F n=3: [order 13] for n>15

%F n=4: [order 55] for n>58

%e Some solutions for n=4 k=4

%e ..0..0..1..0. .0..1..0..2. .0..1..0..1. .0..1..2..2. .0..1..2..0

%e ..1..2..2..1. .0..1..0..2. .1..2..0..1. .0..1..0..1. .0..1..0..1

%e ..0..1..0..1. .2..2..0..1. .1..0..1..2. .0..1..2..1. .2..1..0..1

%e ..2..1..2..1. .0..1..0..2. .1..2..1..0. .1..2..0..1. .0..1..2..1

%Y Column 1 is A007051(n-1).

%Y Column 2 is A231413(n-1).

%Y Row 1 is A021006(n-3).

%Y Row 2 is A280853.

%K nonn,tabl

%O 1,2

%A _R. H. Hardin_, Jan 25 2017

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Last modified March 28 05:39 EDT 2024. Contains 371235 sequences. (Running on oeis4.)