A177506 Primes of the form 4*10^n+1.

5, 41, 401, 4001, 40000000000001

Offset: 1

Author

Vincenzo Librandi, Dec 11 2010

Keywords

• nonn

Links

• Vincenzo Librandi, Table of n, a(n) for n = 1..9
• Makoto Kamada, Prime numbers of the form 400...001.

Crossrefs

Cf. A056806.

Programs

Magma

[a: n in [0..250] | IsPrime(a) where a is 4*10^n+1];

Mathematica

Select[Table[4 10^n + 1, {n, 0, 500}], PrimeQ] (* Vincenzo Librandi Jan 02 2014 *)