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Search: id:A059529
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| A059529 |
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For 1 < x, each c(i) is "multiply" (*) or "divide" (/); a(n) is number of choices for c(0),...,c(n-1) so that 1 c(0) x^1 c(1) x^2,.., c(n-1) x^n is an integer. |
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+0
1
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| 1, 1, 2, 5, 9, 16, 32, 68, 135, 256, 512, 1059, 2110, 4096, 8192, 16745, 33425, 65536, 131072
(list; graph; listen)
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OFFSET
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0,3
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FORMULA
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a(0)=1; for 0<n, a(n) = A058377(n)+2^(n-1).
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EXAMPLE
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x = 3: for n = 2 there are 2 possibilities: 1*3*9=27 and 1/3*9=3. For n = 4 there are 9 possibilities: 1*3*9*27*81 1/3*9*27*81 1*3/9*27*81 1/3/9*27*81 1*3*9/27*81 1*3*9*27/81 1/3*9/27*81 1/3*9*27/81 1*3/9/27*81
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CROSSREFS
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Cf. A058524, A058377.
Sequence in context: A014739 A039946 A130752 this_sequence A119676 A036711 A080740
Adjacent sequences: A059526 A059527 A059528 this_sequence A059530 A059531 A059532
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KEYWORD
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easy,nonn
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AUTHOR
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Naohiro Nomoto (6284968128(AT)geocities.co.jp), Feb 16 2001
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