A058825 Numbers which are both totients and cototients.

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

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: A338361 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