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A214386
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Number of 4X4X4 triangular 0..n arrays with no element lying outside the (possibly reversed) range delimited by its sw and se neighbors, and no element equal to its horizontal neighbors
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1
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16, 890, 11048, 74260, 350232, 1305392, 4107248, 11363940, 28412824, 65439858, 140806952, 286079040, 553378176, 1025850192, 1832212128, 3166557496, 5314833216, 8689668506, 13875533864, 21686539292, 33239546824, 50045674976
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OFFSET
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1,1
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COMMENTS
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Row 4 of A214384
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LINKS
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R. H. Hardin, Table of n, a(n) for n = 1..163
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FORMULA
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Empirical: a(n) = (109/226800)*n^10 + (1531/90720)*n^9 + (6911/30240)*n^8 + (4553/3024)*n^7 + (27071/5400)*n^6 + (34159/4320)*n^5 + (409217/90720)*n^4 - (4937/4536)*n^3 - (22087/12600)*n^2 - (43/126)*n
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EXAMPLE
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Some solutions for n=3
.....3........2........2........2........2........3........2........2
....3.2......1.2......3.0......2.3......2.1......2.3......0.2......1.2
...1.3.0....0.1.2....3.2.0....0.3.2....2.1.2....1.3.0....0.1.2....0.3.2
..0.1.3.0..1.0.3.2..3.0.3.0..0.1.3.1..2.0.1.3..0.3.0.2..0.2.1.2..0.2.3.0
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CROSSREFS
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Sequence in context: A145243 A264125 A272468 * A185561 A283946 A289707
Adjacent sequences: A214383 A214384 A214385 * A214387 A214388 A214389
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KEYWORD
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nonn
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AUTHOR
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R. H. Hardin Jul 14 2012
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STATUS
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approved
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