A201133 Least k such that (5^n + k)*5^n + 1 is a prime number.

1, 3, 3, 23, 7, 3, 3, 5, 7, 59, 15, 35, 45, 23, 3, 5, 45, 57, 15, 5, 49, 17, 87, 105, 45, 5, 21, 45, 43, 129, 3, 243, 57, 39, 57, 23, 21, 53, 25, 77, 15, 95, 87, 137, 33, 21, 51, 113, 49, 27, 7, 371, 45, 417, 51, 275, 253, 87, 75, 473, 109, 35, 229, 237, 253

Offset: 1

Author

Michel Lagneau, Nov 27 2011

Keywords

• nonn

Crossrefs

Cf. A191617, A200920.

Programs

Mathematica

Table[k = 0; While[!PrimeQ[(5^n + k)*5^n + 1], k++]; k, {n, 85}]