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A058524
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Each c(i) is "multiply" (*) or "divide" (/). a(n) is number of choices for c(1), ..., c(n-1) so that 1 c(1) 2 c(2) 3,.., c(n-1) n is an integer.
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3
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1, 1, 1, 2, 2, 8, 8, 13, 21, 77, 77, 128, 128, 354, 641, 1232, 1232, 2677, 2677, 7220, 8951, 25378, 25378, 63680, 113335, 323151, 532358, 1442702, 1442702, 2963955, 2963955, 5307221, 6739508, 21786788, 41416560, 83691901, 83691901, 242224403, 373640477, 669300795, 669300795
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OFFSET
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1,4
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LINKS
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FORMULA
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EXAMPLE
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For n = 4 there are 2 possibilities: 1*2*3*4=24 and 1/2*3*4=6. For n = 9 there are 13 possibilities: 1*2*3*4*5*6*7*8 1/2*3*4*5*6*7*8 1/2/3*4*5*6*7*8 1*2/3*4*5*6*7*8 1*2*3*4*5/6*7*8 1*2*3/4*5*6*7*8 1*2/3/4*5*6*7*8 1/2*3*4*5/6*7*8 1/2*3/4*5*6*7*8 1/2/3/4*5*6*7*8 1*2*3*4*5*6*7/8 1*2/3*4*5*6*7/8 1*2*3/4*5/6*7*8.
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CROSSREFS
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KEYWORD
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nonn,nice
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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