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A007668
phi(n) divides sigma(n) and sigma(n)/n > sigma(m)/m for all m < n.
0
1, 2, 6, 12, 840, 332640
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OFFSET
1,2
LINKS
Table of n, a(n) for n=1..6.
CROSSREFS
Cf.
A020492
,
A004394
.
Sequence in context:
A328448
A074180
A126293
*
A089415
A282974
A181063
Adjacent sequences:
A007665
A007666
A007667
*
A007669
A007670
A007671
KEYWORD
nonn
AUTHOR
Walter Nissen
STATUS
approved
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Last modified March 28 20:05 EDT 2024. Contains 371254 sequences. (Running on oeis4.)