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A033854 Numbers k such that j(k)*ud(k)=phi(k), j(n) = A033831, ud(n) = number of unitary divisors of n (A034444). 0
3, 4, 8, 15, 20, 28, 40, 102, 132, 140, 252, 360, 510, 780 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

If it exists, a(15) > 10^9. - Sean A. Irvine, Jul 20 2020

LINKS

Table of n, a(n) for n=1..14.

CROSSREFS

Cf. A000010 (phi), A033831, A034444.

Sequence in context: A026654 A104370 A310013 * A042981 A337438 A007486

Adjacent sequences:  A033851 A033852 A033853 * A033855 A033856 A033857

KEYWORD

easy,more,nonn

AUTHOR

Naohiro Nomoto

STATUS

approved

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Last modified November 28 11:28 EST 2020. Contains 338720 sequences. (Running on oeis4.)