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A069549
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Smallest composite k such that phi(k) > k*(1-1/n).
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2
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4, 4, 9, 25, 25, 49, 49, 121, 121, 121, 121, 169, 169, 289, 289, 289, 289, 361, 361, 529, 529, 529, 529, 841, 841, 841, 841, 841, 841, 961, 961, 1369, 1369, 1369, 1369, 1369, 1369, 1681, 1681, 1681, 1681, 1849, 1849, 2209, 2209, 2209, 2209, 2809, 2809, 2809
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| Or, least composite k such that k is coprime to the n-1 numbers k+1 ... k+n-1. E.g. a(4) = 25 because 25 is coprime to 26, 27 and 28. - Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Apr 20 2004
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FORMULA
| a(n)=nextprime(n)^2=A007918(n)^2
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CROSSREFS
| Cf. A052349.
Sequence in context: A112683 A192030 A117879 * A118069 A089539 A117416
Adjacent sequences: A069546 A069547 A069548 * A069550 A069551 A069552
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KEYWORD
| easy,nonn
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AUTHOR
| Benoit Cloitre (benoit7848c(AT)orange.fr), Apr 21 2002
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EXTENSIONS
| Edited by David Wasserman (wasserma(AT)spawar.navy.mil), Apr 23 2007
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