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A246895
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Number of length 3+4 0..n arrays with some pair in every consecutive five terms totalling exactly n
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1
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112, 1961, 12544, 57585, 177648, 484297, 1079680, 2256929, 4207600, 7537641, 12554112, 20344081, 31352944, 47355785, 68954368, 98858817, 137838960, 189828649, 255769600, 341151281, 447081712, 580982601, 744111744, 946245985
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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) = 2*a(n-1) +4*a(n-2) -10*a(n-3) -5*a(n-4) +20*a(n-5) -20*a(n-7) +5*a(n-8) +10*a(n-9) -4*a(n-10) -2*a(n-11) +a(n-12)
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EXAMPLE
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Some solutions for n=5
..1....0....3....0....3....1....1....1....1....3....3....1....1....0....1....0
..0....3....0....4....2....0....3....3....3....1....5....0....3....2....1....4
..1....3....4....3....0....5....2....1....2....3....2....4....2....4....1....0
..1....2....1....1....3....4....0....2....0....2....1....0....1....2....2....0
..4....0....1....5....4....2....2....3....2....2....3....1....5....1....4....5
..3....0....5....2....5....1....1....3....1....4....4....4....1....3....2....4
..3....1....1....5....4....5....5....2....4....4....5....3....3....4....0....4
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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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