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A223983
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Number of nX4 0..3 arrays with rows unimodal and columns nondecreasing
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1
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130, 3526, 44803, 358118, 2086196, 9647292, 37395816, 126087157, 379654704, 1040942916, 2637614941, 6248087300, 13964013792, 29662913488, 60254807616, 117633453657, 221649696158, 404535879938, 717351048575, 1239192239626
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OFFSET
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1,1
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COMMENTS
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Column 4 of A223987
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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) = (3551/47900160)*n^12 + (89357/39916800)*n^11 + (132341/4354560)*n^10 + (177787/725760)*n^9 + (1892753/1451520)*n^8 + (5834147/1209600)*n^7 + (11057083/870912)*n^6 + (17370313/725760)*n^5 + (6973385/217728)*n^4 + (26874943/907200)*n^3 + (186503/10395)*n^2 + (8831/1386)*n + 1
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EXAMPLE
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Some solutions for n=3
..1..1..0..0....0..1..0..0....1..0..0..0....1..1..1..2....0..1..1..0
..1..2..0..0....1..3..2..0....1..3..2..0....1..1..1..2....0..2..3..2
..2..2..1..1....3..3..3..2....2..3..3..3....1..2..2..3....1..3..3..3
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CROSSREFS
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Sequence in context: A168124 A224169 A223860 * A224060 A224046 A224277
Adjacent sequences: A223980 A223981 A223982 * A223984 A223985 A223986
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KEYWORD
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nonn
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AUTHOR
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R. H. Hardin Mar 30 2013
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STATUS
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approved
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