A215446 Numbers k such that 11^k + k^11 - 1 is prime.

1, 7, 27, 43, 87, 223, 11589

Offset: 1

Author

Vincenzo Librandi, Sep 06 2012

Keywords

• nonn
• hard
• more

Comments

a(8) > 2*10^5. - Robert Price, Nov 08 2014

Programs

Magma

[k: k in [0..2000] | IsPrime(11^k + k^11 - 1)];

Mathematica

Select[Range[0, 5000], PrimeQ[11^# + #^11 - 1] &]

PARI

is(n)=isprime(11^n+n^11-1) \\ Charles R Greathouse IV, Feb 17 2017

Extensions

a(7) from Robert Price, Mar 15 2014