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A202884
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Number of nX3 0..2 arrays with every nonzero element less than or equal to some horizontal or vertical neighbor
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1
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9, 265, 5493, 109119, 2223723, 45332961, 922352267, 18770352883, 382034229103, 7775324294349, 158245814846079, 3220677883878199, 65548442623908105, 1334066131775449299, 27151407675046583355, 552595506856781602893
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OFFSET
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1,1
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COMMENTS
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Column 3 of A202889
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LINKS
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R. H. Hardin, Table of n, a(n) for n = 1..210
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FORMULA
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Empirical: a(n) = 22*a(n-1) -73*a(n-2) +857*a(n-3) -1769*a(n-4) +12671*a(n-5) +21249*a(n-6) +11663*a(n-7) -43772*a(n-8) -233931*a(n-9) -841906*a(n-10) -520038*a(n-11) -711742*a(n-12) +722084*a(n-13) +4070420*a(n-14) +788112*a(n-15) -3390432*a(n-16) -1162224*a(n-17) +645120*a(n-18) +248832*a(n-19)
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EXAMPLE
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Some solutions for n=3
..1..1..1....1..2..2....0..0..2....0..2..2....2..1..1....1..0..0....0..0..2
..1..0..2....1..2..1....0..1..2....0..1..1....2..1..0....2..2..2....2..2..2
..1..2..2....0..2..0....0..2..2....2..2..1....1..1..0....2..1..1....0..2..2
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CROSSREFS
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Sequence in context: A003387 A177393 A081059 * A188963 A306535 A144684
Adjacent sequences: A202881 A202882 A202883 * A202885 A202886 A202887
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KEYWORD
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nonn
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AUTHOR
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R. H. Hardin Dec 25 2011
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STATUS
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approved
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