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 A058825 Numbers which are both totients and cototients. 1
 1, 2, 4, 6, 8, 12, 16, 18, 20, 22, 24, 28, 30, 32, 36, 40, 42, 44, 46, 48, 54, 56, 60, 64, 66, 70, 72, 78, 80, 82, 84, 88, 92, 96, 102, 104, 106, 108, 110, 112, 120, 126, 128, 132, 136, 138, 140, 144, 148, 150, 156, 160, 162, 164, 166, 168, 176, 178, 180, 184, 190 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Donovan Johnson, Table of n, a(n) for n = 1..10000 FORMULA Intersection(A002202, A051953). EXAMPLE 24 is here because 24 = phi(72) = 44-phi(44) = 44-20 = cototient(44). CROSSREFS Cf. A000010, A051953, A005277, A005278, A002020, A058763. Sequence in context: A094109 A090404 A015937 * A087086 A301587 A319796 Adjacent sequences:  A058822 A058823 A058824 * A058826 A058827 A058828 KEYWORD nonn AUTHOR Labos Elemer, Jan 04 2001 EXTENSIONS Offset corrected by Donovan Johnson, Nov 17 2013 STATUS approved

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Last modified December 10 18:10 EST 2019. Contains 329901 sequences. (Running on oeis4.)