A109376 Numbers k such that k * (sum of the digits of k raised to their own power) + 1 is prime and sets a new record for number of digits.

1, 11, 20, 33, 35, 36, 75, 79, 390, 1991, 9199, 91899, 699949, 5299999, 39999999, 428999999, 3699949999

Offset: 1

Author

Jason Earls, Aug 25 2005

Keywords

• base
• more
• nonn

Crossrefs

Cf. A109372.

Extensions

a(15) from Owen Whitby, Sep 11 2013

a(16)-a(17) from Michael S. Branicky, May 02 2024