A090887 Irregular primes the indices of whose indices are irregular primes of order two.

12923, 19577, 26021, 41203, 41953, 53437, 65309, 68399, 117511, 134731, 137713, 142327, 149861, 155821, 164701, 167887, 192347, 197647, 216901, 224911, 231323, 236063, 246049, 250031, 268999, 271723, 273787, 289543, 317959, 331519, 338141

Offset

1,1

Comments

The number of primes in this sequence is infinite.

Links

Table of n, a(n) for n=1..31.

Example

37 is the first irregular prime, 613 is the 37th irregular prime, i.e. iprime[iprime[1]] = 613 and 12923 is the 613th irregular prime.

Crossrefs

Sequence in context: A162895 A256746 A086004 * A246890 A145333 A190468

Adjacent sequences: A090884 A090885 A090886 * A090888 A090889 A090890

Keyword

easy,nonn

Author

Cino Hilliard, Feb 12 2004

Status

approved