A116046 n+phi(n)+phi(phi(n)) is a semiprime (A001358).

2, 3, 6, 7, 8, 11, 14, 18, 23, 27, 29, 31, 34, 37, 38, 42, 45, 47, 53, 55, 59, 63, 65, 66, 69, 73, 74, 83, 89, 90, 91, 93, 103, 105, 107, 109, 110, 117, 119, 123, 125, 127, 129, 130, 131, 138, 139, 143, 145, 150, 151, 157, 167, 174, 175, 179, 182, 183, 185, 186

Offset

1,1

Links

Table of n, a(n) for n=1..60.

Example

103+phi(103)+phi(phi(103)) = 3*79.

Crossrefs

Cf. A001358, A116045.

Sequence in context: A304028 A155152 A098740 * A069579 A327176 A065193

Adjacent sequences: A116043 A116044 A116045 * A116047 A116048 A116049

Keyword

nonn

Author

Giovanni Resta, Feb 13 2006

Status

approved