A129614 a(n) is the smallest natural number m such that 3^(3^k) + m is prime for k=0,1,...,n.

2, 2, 4, 16, 346, 390410, 390410, 34712918410, 40501164004

Offset

0,1

Comments

Next term is greater than 2*10^8.

Links

Table of n, a(n) for n=0..8.

Example

For k=0,1,...,6 3^3^k + 390410 are prime and 390410 is the smallest number with this property so a(6)=390410.

Crossrefs

Cf. A129613, A129615.

Sequence in context: A168089 A165420 A171163 * A070283 A070282 A267218

Adjacent sequences: A129611 A129612 A129613 * A129615 A129616 A129617

Keyword

hard,more,nonn

Author

Farideh Firoozbakht, May 13 2007, Jun 01 2007

Status

approved