%I A045616
%S A045616 3,487,56598313
%N A045616 Primes p such that decimal fraction 1/p has same period length as 1/p^2.
%C A045616 No further terms up to 2*10^11 - Helmut Richter (richter(AT)lrz.de), 
               May 17 2004
%H A045616 Helmut Richter, <a href="http://www.lrz-muenchen.de/~hr/numb/period.html">
               Title? (1)</a>
%H A045616 Helmut Richter, <a href="http://www.lrz-muenchen.de/~hr/numb/fact486.html">
               Title? (2)</a>
%F A045616 Primes p such that 10^(p-1) == 1 (mod p^2)
%Y A045616 Analogous sequence for base 2 instead of 10 (Wieferich primes): A001220. 
               First members of analogous sequences for all bases: A039951.
%Y A045616 Sequence in context: A157587 A054702 A140015 this_sequence A142801 A057632 
               A024045
%Y A045616 Adjacent sequences: A045613 A045614 A045615 this_sequence A045617 A045618 
               A045619
%K A045616 bref,hard,nonn,nice
%O A045616 1,1
%A A045616 Helmut Richter (richter(AT)lrz.de)