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A088032
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Smallest number k such that k^n -1 is divisible by an n-th power. a(n) = A088031(n)^(1/n).
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2
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3, 3, 9, 3, 33, 31, 129, 31, 513, 511, 2049, 1023, 8193, 8191, 32769, 4095, 131073, 131071, 524289, 262143, 2097153, 2097151, 8388609, 2097151
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OFFSET
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1,1
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COMMENTS
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For 2 < n < 18, if n is odd then a(n) = 2^n+1 and if n is even then a(n) = 2^(n-A007814(n))-1. - David Wasserman, Jun 21 2005
The above also holds for 19 < n < 24. If true for n >= 25 then a(25..29) = 33554433, 33554431, 134217729, 67108863, 536870913. - Lars Blomberg, Feb 09 2016
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LINKS
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EXAMPLE
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a(4) = 81 = 3^4 and 81-1 = 80 == 0 (mod 2^4).
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CROSSREFS
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KEYWORD
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more,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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