A180644 Numbers n such that 3+phi(n)^2 is a prime

3, 4, 5, 6, 8, 10, 11, 12, 15, 16, 20, 22, 23, 24, 29, 30, 46, 53, 58, 71, 85, 106, 107, 113, 128, 131, 136, 141, 142, 145, 160, 170, 173, 179, 187, 188, 192, 204, 205, 213, 214, 226, 232, 240, 257, 262, 282, 284, 290, 317, 328, 346, 348, 352, 358, 374, 400, 410

Offset

1,1

Links

Table of n, a(n) for n=1..58.

Example

a(15)=29 since 3+phi(29)^2=3+28^2=787 is prime

Crossrefs

Cf. A000010

Sequence in context: A039031 A047309 A121502 * A202110 A267858 A108943

Adjacent sequences: A180641 A180642 A180643 * A180645 A180646 A180647

Keyword

nonn

Author

Carmine Suriano, Sep 14 2010

Status

approved