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A250135
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Number of length n+2 0..3 arrays with the medians of every three consecutive terms nondecreasing
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1
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64, 204, 632, 1959, 5696, 16104, 45232, 124249, 335328, 897523, 2377452, 6233295, 16229424, 41987965, 107948004, 276101588, 703049528, 1782693579, 4503485124, 11339512465, 28466148864, 71263715430, 177963467480, 443410709998
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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) = 4*a(n-1) -6*a(n-2) +24*a(n-3) -57*a(n-4) +52*a(n-5) -170*a(n-6) +256*a(n-7) -98*a(n-8) +560*a(n-9) -340*a(n-10) -80*a(n-11) -977*a(n-12) -372*a(n-13) +48*a(n-14) +624*a(n-15) +788*a(n-16) +192*a(n-17) -96*a(n-18) -288*a(n-19) -144*a(n-20)
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EXAMPLE
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Some solutions for n=6
..0....1....0....2....0....1....1....0....0....0....0....0....1....0....0....0
..0....0....0....1....3....0....0....1....2....0....1....1....2....1....1....2
..3....1....1....0....3....0....1....1....3....0....0....1....0....2....3....1
..0....1....2....3....0....2....2....3....0....0....0....0....3....1....2....1
..2....1....2....2....3....3....2....0....2....3....3....1....3....1....1....1
..2....1....0....2....3....2....2....1....3....3....1....1....3....1....2....1
..2....0....3....1....3....1....3....1....2....0....0....1....0....3....3....2
..2....1....2....2....3....2....0....2....1....3....2....0....3....3....3....3
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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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