A033856 Numbers k such that j(k)*phi(k) = sigma(phi(k)), j(k) = A033831(k).

14, 58, 175, 244, 833, 1017, 1348, 8653, 33263, 33497, 33611, 34099, 34151, 34529, 34771, 36281, 36449, 36743, 37367, 37373, 38311, 38695, 38735, 38915, 39035, 39263, 39295, 39431, 39995, 41015, 41635, 42119, 46209, 46617, 46731, 47067, 49911, 50007, 50871

Offset

1,1

Links

Amiram Eldar, Table of n, a(n) for n = 1..406

Mathematica

j[n_] := DivisorSum[n, 1&, # > 2 && n/# < #-1 &]; aQ[n_] := j[n]*(p = EulerPhi[ n]) == DivisorSigma[1, p]; Select[Range[10^4], aQ] (* Amiram Eldar, Jul 01 2019 *)

Crossrefs

Cf. A000010, A000203, A033831, A033855.

Sequence in context: A041376 A063537 A084195 * A143861 A100174 A372675

Adjacent sequences: A033853 A033854 A033855 * A033857 A033858 A033859

Keyword

easy,nonn

Author

Naohiro Nomoto

Extensions

More terms from Amiram Eldar, Jul 01 2019

Status

approved