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A068005 Numbers n such that n*sigma(n) > phi(n)*prime(n). 1
2, 3, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 28, 30, 36, 40, 42, 48, 50, 54, 56, 60, 66, 70, 72, 78, 80, 84, 90, 96, 100, 102, 108, 114, 120, 126, 132, 138, 140, 144, 150, 156, 160, 162, 168, 174, 180, 186, 192, 198, 204, 210, 216, 220, 222, 228, 234, 240, 252, 264
(list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
MATHEMATICA
Select[Range@265, #*DivisorSigma[1, #] > EulerPhi[#]*Prime[#] &] (* Ivan Neretin, Dec 28 2016 *)
CROSSREFS
Sequence in context: A371925 A084925 A045718 * A055721 A064376 A283808
KEYWORD
easy,nonn
AUTHOR
Benoit Cloitre, Mar 22 2002
STATUS
approved

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Last modified September 18 10:04 EDT 2024. Contains 375999 sequences. (Running on oeis4.)