A167281 Primes containing the string 555.

5557, 15551, 15559, 45553, 45557, 55501, 55511, 55529, 55541, 55547, 55579, 55589, 65551, 65557, 75553, 75557, 105557, 115553, 125551, 135559, 155501, 155509, 155521, 155537, 155539, 155557, 155569, 155579, 155581, 155593, 155599, 165551

Offset: 1

Author

Vincenzo Librandi, Nov 01 2009

Keywords

• nonn
• base

Links

• Vincenzo Librandi, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A166571-A166573, A166579-A166582.

Programs

Mathematica

p555Q[n_] := Module[{idn=IntegerDigits[n]}, MemberQ[Partition[idn, 3, 1], {5, 5, 5}]]; Select[Prime[Range[16000]], p555Q] (* Vincenzo Librandi, Sep 15 2013 *)

Formula

a(n) ~ n log n. - Charles R Greathouse IV, Nov 01 2022