A134621 Numbers such that the arithmetic mean of the 4th power of their prime factors (taken with multiplicity) is a prime.

15, 28, 39, 48, 51, 65, 68, 76, 77, 85, 87, 93, 111, 119, 133, 141, 143, 148, 155, 161, 175, 187, 189, 209, 212, 215, 221, 225, 235, 244, 275, 287, 295, 301, 315, 316, 320, 323, 329, 355, 393, 403, 404, 411, 428, 437, 447, 451, 455, 481, 505, 508, 515, 517

Offset

1,1

Links

Hieronymus Fischer, Table of n, a(n) for n = 1..10000

Example

a(3)=39, since 39=3*13 and (3^4+13^4)/2=14321 which is prime.

Crossrefs

Cf. A001597, A025475, A134333, A134344, A134376.

Cf. A134600, A134602, A134605, A134608, A134613, A134617, A134619.

Sequence in context: A178958 A099808 A291054 * A106499 A043108 A045192

Adjacent sequences: A134618 A134619 A134620 * A134622 A134623 A134624

Keyword

nonn

Author

Hieronymus Fischer, Nov 11 2007

Extensions

Minor edits by Hieronymus Fischer, May 06 2013

Status

approved