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A069858
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1/n has period 4 in base 10.
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0
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101, 202, 303, 404, 505, 606, 808, 909, 1010, 1111, 1212, 1515, 1616, 1818, 2020, 2222, 2424, 2525, 3030, 3232, 3333, 3636, 4040, 4444, 4545, 4848, 5050, 5555, 6060, 6464, 6666, 7272, 7575, 8080, 8888, 9090, 9696, 9999, 10100, 11110, 12120, 12625
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OFFSET
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1,1
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LINKS
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FORMULA
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Numbers of the form a*b*c where a is in {101, 303, 909, 1111, 3333, 9999}, b is a power of 2 and c is a power of 5.
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EXAMPLE
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1212 is in the sequence since 1/1212=0.0008250825082508250825082508250....
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MATHEMATICA
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Select[Range[13000], Length[RealDigits[1/#][[1, -1]]]==4&] (* Harvey P. Dale, Jun 30 2017 *)
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CROSSREFS
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KEYWORD
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base,nonn
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AUTHOR
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STATUS
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approved
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