OFFSET
1,1
LINKS
Paul Bourdelais,A Generalized Repunit Conjecture
J. Brillhart et al.,Factorizations of b^n +- 1,Contemporary Mathematics, Vol. 22, Amer. Math. Soc., Providence, RI, 3rd edition, 2002.
H. Dubner and T. Granlund,Primes of the Form (b^n+1)/(b+1),J. Integer Sequences, 3 (2000), #P00.2.7.
H. Lifchitz,Mersenne and Fermat primes field
Eric Weisstein's World of Mathematics,Repunit
MATHEMATICA
lst={}; Do[p=(11^n+1)/12; If[PrimeQ[p], AppendTo[lst, n]], {n, 7!}]; lst (*Vladimir Joseph Stephan Orlovsky,Sep 29 2008 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane,Sep 15 2000
EXTENSIONS
a(8) corresponds to a probable prime discovered byPaul Bourdelais,Feb 12 2010
a(9) corresponds to a probable prime discovered byPaul Bourdelais,Sep 30 2013
a(10) byPaul Bourdelais,Jul 19 2021
STATUS
approved