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A140695
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A number n is included if the number of positive divisors of n is neither a divisor of n nor is coprime to n.
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1
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6, 10, 14, 20, 22, 26, 28, 30, 32, 34, 38, 42, 44, 45, 46, 48, 50, 52, 54, 58, 62, 63, 66, 68, 70, 74, 75, 76, 78, 82, 86, 90, 92, 94, 98, 99, 102, 106, 110, 112, 114, 116, 117, 118, 120, 122, 124, 126, 130, 134, 138, 140, 142, 144, 146, 147, 148, 150, 153, 154, 158
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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EXAMPLE
| 36 has 9 divisors. 9 divides 36. So 36 is not in the sequence. 23 has 2 divisors. 2 is coprime to 23. So 23 is not in the sequence. On the other hand, 42 has 8 divisors. 8 does not divide 42. And 8 is not coprime to 42. So 42 is in the sequence.
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MATHEMATICA
| Select[Range[200], 1 < Mod[ #, Length[Divisors[ # ]]] && GCD[ #, Length[Divisors[ # ]]] > 1 &] - Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), May 30 2008
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CROSSREFS
| Cf. A140696.
Sequence in context: A007944 A200269 A006617 * A085681 A068919 A060650
Adjacent sequences: A140692 A140693 A140694 * A140696 A140697 A140698
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KEYWORD
| nonn
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AUTHOR
| Leroy Quet May 23 2008
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EXTENSIONS
| More terms from Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), May 30 2008
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