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A140887
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Number of nonprimes in [30n - 30, 30n] coprime to 30.
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1
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1, 1, 1, 2, 3, 2, 3, 2, 3, 3, 4, 2, 3, 4, 2, 3, 3, 6, 3, 3, 3, 2, 4, 4, 4, 3, 5, 2, 4, 4, 4, 4, 4, 3, 3, 4, 2, 5, 5, 4, 3, 4, 4, 2, 6, 5, 5, 3, 4, 1, 6, 3, 4, 2, 5, 4, 4, 5, 4, 4, 5, 6, 1, 5, 5, 5, 3, 3, 5, 3, 5, 3, 6, 5, 4, 4, 3, 5, 4, 1, 5, 4, 5, 7, 3, 5, 5, 5, 4, 1, 3, 4, 5, 3, 5, 4, 4, 5, 4, 6, 4, 5, 3, 6, 6
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,4
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COMMENTS
| For almost all n, a(n) = phi(30) = 8. It first attains this value at a(361).
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EXAMPLE
| {1,7,11,13,17,19,23,29} are coprime to 30 in [0, 30]; 1 is nonprime, so a(1) = 1.
{31,37,41,43,47,49,53,59} are coprime to 30 in [30, 60]; 49 is nonprime, so a(2) = 1.
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CROSSREFS
| Cf. A007775.
Sequence in context: A086411 A105528 A076225 * A132423 A071995 A114108
Adjacent sequences: A140884 A140885 A140886 * A140888 A140889 A140890
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KEYWORD
| nonn,easy,less
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AUTHOR
| Juri-Stepan Gerasimov (2stepan(AT)rambler.ru), Jul 06 2008
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EXTENSIONS
| Rewritten and extended by Charles R Greathouse IV (charles.greathouse(AT)case.edu), Mar 26 2010
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