a(n) is the least integer k > 1 such that 1 + k^(5^n) + k^(2*5^n) + k^(3*5^n) + k^(4*5^n) is prime.
A206418
a(n) is the least integer k > 1 such that 1 + k^(5^n) + k^(2*5^n) + k^(3*5^n) + k^(4*5^n) is prime.
Terms
- a(0) =2a(1) =22a(2) =127a(3) =55a(4) =1527a(5) =18453a(6) =5517
External references
- oeis: A206418