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A274857
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Number of nX7 0..2 arrays with no element equal to any value at offset (-1,0) (0,-1) or (-2,-2) and new values introduced in order 0..2.
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1
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32, 729, 542, 2585, 12102, 58775, 289494, 1426688, 7031552, 34766640, 172447382, 856198165, 4249077675, 21078145330, 104568950459, 518896515145, 2575174869347, 12779650282427, 63417621140877, 314701428995532
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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) = 21*a(n-1) -209*a(n-2) +1330*a(n-3) -6059*a(n-4) +20839*a(n-5) -55739*a(n-6) +118287*a(n-7) -202495*a(n-8) +284119*a(n-9) -331806*a(n-10) +326718*a(n-11) -273224*a(n-12) +193798*a(n-13) -115270*a(n-14) +56258*a(n-15) -21837*a(n-16) +6481*a(n-17) -1404*a(n-18) +210*a(n-19) -20*a(n-20) +a(n-21) for n>24
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EXAMPLE
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Some solutions for n=4
..0..1..2..0..1..0..1. .0..1..0..1..2..0..1. .0..1..0..2..1..2..1
..1..2..0..1..0..1..2. .2..0..1..2..0..1..2. .1..0..2..0..2..1..0
..2..0..2..0..1..2..0. .0..1..2..0..1..2..0. .0..2..1..2..1..0..2
..1..2..0..1..2..0..1. .1..2..0..2..0..1..2. .1..0..2..1..0..2..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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