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A197777
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Number of nX3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 3,2,1,1,1 for x=0,1,2,3,4
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1
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2, 14, 67, 338, 1646, 8085, 39748, 194964, 957860, 4707712, 23133353, 113660751, 558419575, 2743624616, 13480339775, 66233515886, 325425835373, 1598912188088, 7855923951863, 38598502682366, 189646074869215, 931788192551971
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OFFSET
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1,1
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COMMENTS
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Every 0 is next to 0 3's, every 1 is next to 1 2's, every 2 is next to 2 1's, every 3 is next to 3 1's, every 4 is next to 4 1's
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LINKS
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FORMULA
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Empirical: a(n) = 2*a(n-1) +4*a(n-2) +26*a(n-3) +58*a(n-4) +224*a(n-5) +408*a(n-6) +355*a(n-7) -572*a(n-8) -2544*a(n-9) -4095*a(n-10) -5378*a(n-11) -3143*a(n-12) -80*a(n-13) +6397*a(n-14) +7947*a(n-15) +5742*a(n-16) +6380*a(n-17) -5069*a(n-18) -7405*a(n-19) +2109*a(n-20) -9374*a(n-21) +209*a(n-22) +6536*a(n-23) -6126*a(n-24) +2689*a(n-25) -279*a(n-26) -618*a(n-27) +1806*a(n-28) -64*a(n-29) +218*a(n-30) +206*a(n-31) -46*a(n-32) +10*a(n-33) -4*a(n-35)
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EXAMPLE
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Some solutions for n=4
..1..2..1....0..0..0....1..2..1....0..0..0....1..1..2....0..0..0....1..2..1
..0..0..0....0..1..1....0..0..1....0..0..0....2..1..1....0..0..0....1..2..1
..0..2..1....1..2..2....1..0..2....2..1..1....2..1..1....0..1..0....0..0..1
..0..1..0....0..0..1....2..1..1....1..1..2....1..1..2....1..2..0....0..1..2
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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