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A164649
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Numbers n such that sigma(n)/phi(n) = 36/25.
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1
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5797, 10153, 20377, 50953, 383719, 405449, 446039, 486421, 608399, 973709, 1321529, 1521311, 3086369, 3228511, 3451877, 3529813, 3859513, 4552373, 4767721, 5827679, 6194321, 6479599, 6724039, 6927893, 7038241, 7919197
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| A subsequence of A011257. See A164646-A164650 for related sequences.
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PROG
| (PARI) for( n=1, 1e7, sigma(n)==36/25*eulerphi(n) && print1(n", "))
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CROSSREFS
| Cf. A000010 (=phi), A000203 (=sigma), A068390 (sigma/phi=4), A163667 (sigma/phi=9), A164646-A164650.
Sequence in context: A004973 A114361 A098476 * A206655 A104284 A131494
Adjacent sequences: A164646 A164647 A164648 * A164650 A164651 A164652
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KEYWORD
| nonn
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AUTHOR
| M. F. Hasler (www.univ-ag.fr/~mhasler), Aug 22 2009
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EXTENSIONS
| More terms from Sean A. Irvine (sairvin(AT)xtra.co.nz), May 17 2010
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