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A250648
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Number of length 4+1 0..n arrays with the sum of the maximum of each adjacent pair multiplied by some arrangement of +-1 equal to zero
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1
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20, 125, 476, 1293, 2954, 5901, 10766, 18305, 29478, 45361, 67364, 96961, 135976, 186445, 250688, 331213, 431054, 553277, 701474, 879553, 1091754, 1342593, 1637320, 1981153, 2380028, 2840317, 3368740, 3972397, 4659346, 5437517, 6315766
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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) = a(n-1) +2*a(n-2) +a(n-3) -4*a(n-4) -5*a(n-5) +3*a(n-6) +6*a(n-7) +3*a(n-8) -5*a(n-9) -4*a(n-10) +a(n-11) +2*a(n-12) +a(n-13) -a(n-14)
Empirical for n mod 6 = 0: a(n) = (2/15)*n^5 + (403/162)*n^4 + (532/81)*n^3 + (17/3)*n^2 + (124/45)*n + 1
Empirical for n mod 6 = 1: a(n) = (2/15)*n^5 + (403/162)*n^4 + (532/81)*n^3 + (151/27)*n^2 + (1361/405)*n + (301/162)
Empirical for n mod 6 = 2: a(n) = (2/15)*n^5 + (403/162)*n^4 + (532/81)*n^3 + (17/3)*n^2 + (1036/405)*n + (49/81)
Empirical for n mod 6 = 3: a(n) = (2/15)*n^5 + (403/162)*n^4 + (532/81)*n^3 + (17/3)*n^2 + (169/45)*n + (5/2)
Empirical for n mod 6 = 4: a(n) = (2/15)*n^5 + (403/162)*n^4 + (532/81)*n^3 + (151/27)*n^2 + (956/405)*n + (29/81)
Empirical for n mod 6 = 5: a(n) = (2/15)*n^5 + (403/162)*n^4 + (532/81)*n^3 + (17/3)*n^2 + (1441/405)*n + (341/162)
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EXAMPLE
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Some solutions for n=6
..0....0....3....2....1....2....3....0....0....1....1....1....5....0....1....4
..2....5....6....2....4....6....2....6....4....6....3....3....6....6....6....0
..5....1....6....0....1....5....4....1....3....0....0....3....5....4....5....2
..2....2....6....5....6....5....3....6....4....5....6....4....5....6....5....1
..2....1....5....1....5....1....3....4....1....2....2....1....0....4....3....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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