A250296 Number n such that A057137(n) is a semiprime.

3, 4, 7, 11, 17, 27, 31, 124, 157, 247

Offset

1,1

Comments

First unknown: 397.

Links

Table of n, a(n) for n=1..10.

Example

a(4) = 11 so A057137(11) = 12345678901 = 857 * 14405693 is a semiprime.

Crossrefs

Cf. A120819, A057137, A046461.

Sequence in context: A069950 A147869 A319106 * A279785 A100581 A093090

Adjacent sequences: A250293 A250294 A250295 * A250297 A250298 A250299

Keyword

nonn,base

Author

Eric Chen, Dec 25 2014

Status

approved