%I A141350
%S A141350 121,703,3281,8401,12403,31621,44287,47197,55969
%N A141350 Overpseudoprimes of base 3.
%C A141350 If h_3(n) is the multiplicative order of 3 modulo n, r_3(n) is the number 
               of cyclotomic cosets of 3 modulo n then, by the definition, n is 
               an overpseudoprime of base 3 if h_3(n)*r_3(n)+1=n. These numbers 
               are in A020229.
%C A141350 In particular, if n is squarefree such that its prime factorization is 
               n=p_1*...*p_k, then n is overpseudoprime of base 3 iff h_3(p_1)=...=h_3(p_k).
%D A141350 V. Shevelev, Overpseudoprimes, Mersenne Numbers and Wieferich Primes, 
               arxiv.org/abs/0806.3412
%Y A141350 Cf. A141232 A137576 A001262 A020229 A062117 A006694.
%Y A141350 Sequence in context: A014749 A048950 A020229 this_sequence A120353 A036928 
               A088171
%Y A141350 Adjacent sequences: A141347 A141348 A141349 this_sequence A141351 A141352 
               A141353
%K A141350 nonn
%O A141350 1,1
%A A141350 Vladimir Shevelev (shevelev(AT)bgu.ac.il), Jun 27 2008, corrected Sep 
               07 2008