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A055163 (n - Phi(n)) | Sigma(n) for composite n. 1
6, 10, 14, 22, 26, 34, 38, 46, 58, 62, 74, 82, 86, 94, 99, 106, 118, 122, 134, 142, 146, 158, 166, 168, 178, 187, 194, 202, 206, 214, 218, 226, 254, 262, 274, 278, 298, 302, 314, 326, 334, 346, 358, 362, 382, 386, 394, 398, 422, 446, 454, 458, 466, 478, 482 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
MATHEMATICA
Do[ If[ !PrimeQ[ n ], If[ Mod[ DivisorSigma[ 1, n ], n-EulerPhi[ n ] ] == 0, Print[ n ] ], {n, 1, 500} ]
Select[Range[500], CompositeQ[#]&&Divisible[DivisorSigma[1, #], #-EulerPhi[ #]]&] (* Harvey P. Dale, May 16 2016 *)
CROSSREFS
Sequence in context: A080784 A072978 A369966 * A342192 A119431 A207574
KEYWORD
easy,nonn
AUTHOR
Robert G. Wilson v, Jun 30 2000
STATUS
approved

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Last modified April 18 02:22 EDT 2024. Contains 371767 sequences. (Running on oeis4.)