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A239181
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Number of (3+1)X(n+1) 0..2 arrays with no element greater than all horizontal neighbors or equal to all vertical neighbors
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1
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36, 676, 9604, 142884, 2286144, 36216324, 570732100, 8995763716, 141880288900, 2237680908544, 35289896680900, 556546510372644, 8777179394306404, 138423129725708100, 2183042242048352400, 34428300464251842724
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OFFSET
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1,1
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COMMENTS
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LINKS
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FORMULA
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Empirical: a(n) = 15*a(n-1) +148*a(n-3) +922*a(n-4) -3635*a(n-5) -1087*a(n-6) +8846*a(n-7) -4276*a(n-8) +5182*a(n-9) +542*a(n-10) -22842*a(n-11) +14936*a(n-12) -4238*a(n-13) +2914*a(n-14) +1585*a(n-15) -189*a(n-16) +354*a(n-17) -18*a(n-18) -50*a(n-19) +13*a(n-20) -a(n-21)
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EXAMPLE
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Some solutions for n=4
..0..0..0..2..2....1..1..0..1..1....0..1..2..2..1....0..0..0..1..1
..1..2..2..0..0....0..0..2..2..0....2..2..0..0..0....1..1..2..2..0
..0..1..1..2..2....2..2..2..2..1....1..2..2..2..0....2..2..2..0..0
..2..2..0..1..1....0..1..1..0..0....0..0..1..1..1....1..1..1..1..1
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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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