A070213 Numbers k such that A056542(k) is prime.

4, 8, 18, 20, 70

Offset: 1

Author

Tom Mueller (muel4503(AT)uni-trier.de), May 07 2002

Keywords

• nonn
• hard
• more

Comments

The 6th term (if it exists) is larger than 1019.

No additional primes for n < 14000. - T. D. Noe, Jul 07 2005

a(6) > 25000. - Michael S. Branicky, Apr 16 2025

Links

• Tom Mueller, Prime and Composite Terms in Sloane's Sequence A056542, Journal of Integer Sequences, Vol. 8 (2005), Article 05.3.3.

Crossrefs

Cf. A056542.

Extensions

a(5) from Tom Mueller (muel4503(AT)uni-trier.de), Oct 30 2004

Name clarified by Sean A. Irvine, Jun 02 2024