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A147569
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a(n) = sigma(A020492(n)).
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1
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1, 3, 4, 12, 28, 24, 24, 72, 48, 96, 120, 144, 168, 192, 336, 480, 360, 576, 480, 720, 720, 576, 720, 1344, 1440, 1440, 1440, 1872, 1728, 1920, 1680, 2880, 2016, 1440, 2880, 2880, 2880, 3600, 5760, 4320, 5040, 7200, 6720, 7392, 8064, 8640, 8640, 5760, 5616
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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EXAMPLE
| a(5) = sigma(A020492(5)) = sigma(12) = 28.
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PROG
| (MAGMA) [ SumOfDivisors(n): n in [1..3500] | SumOfDivisors(n) mod EulerPhi(n) eq 0 ]; [From Klaus Brockhaus, Nov 09 2008]
(PARI) {for(n=1, 3500, a=sigma(n); if(a%eulerphi(n)==0, print1(a, ", ")))} [From Klaus Brockhaus, Nov 09 2008]
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CROSSREFS
| Cf. A020492 A023897 A147570
Sequence in context: A197459 A000207 A002986 * A090660 A000208 A079154
Adjacent sequences: A147566 A147567 A147568 * A147570 A147571 A147572
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KEYWORD
| easy,nonn
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AUTHOR
| Enoch Haga (Enokh(AT)comcast.net), Nov 07 2008
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EXTENSIONS
| Edited by Klaus Brockhaus, Nov 09 2008
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