A138647 Primes of form (5^n+1)/6.

521, 11293772630057337854244300009061892827351888021, 6573840876841765045097738044023218580610053625908525039752324422200521, 164346021921044126127443451100580464515251340647713125993808110555013021

Offset: 1

Author

Vladimir Joseph Stephan Orlovsky, May 15 2008

Keywords

• nonn

Programs

Mathematica

a={};Do[x=(5^n+1)/6;If[PrimeQ[x],AppendTo[a,x]],{n,0,12^2}];a
Select[(5^Range[0,200]+1)/6,PrimeQ] (* Harvey P. Dale, Jul 18 2011 *)