%I A083736
%S A083736 561,29341,46657,75361,115921,162401,252601,294409,314821,334153,340561,
%T A083736 399001,410041,488881,512461,530881,552721,656601,658801,710533,721801,
%U A083736 852841,1024651,1141141,1152271,1168513,1193221,1461241,1569457,1615681
%N A083736 Pseudoprimes to bases 2,5 and 7.
%H A083736 R. J. Mathar, <a href="b083736.txt">Table of n, a(n) for n=1..81</a>
%H A083736 F. Richman, <a href="http://www.math.fau.edu/Richman/carm.htm">Primality 
               testing with Fermat's little theorem</a>
%F A083736 a(n) = n-th positive integer k(>1) such that 2^(k-1) = 1 (mod k), 5^(k-1) 
               = 1 (mod k) and 7^(k-1) = 1 (mod k)
%e A083736 a(1)=561 since it is the first number such that 2^(k-1) = 1 (mod k), 
               5^(k-1) = 1 (mod k) and 7^(k-1) = 1 (mod k)
%o A083736 Assembly
%Y A083736 Sequence in context: A110889 A063400 A141706 this_sequence A006931 A097061 
               A139089
%Y A083736 Adjacent sequences: A083733 A083734 A083735 this_sequence A083737 A083738 
               A083739
%K A083736 easy,nonn
%O A083736 1,1
%A A083736 Serhat Sevki Dincer (sevki(AT)ug.bilkent.edu.tr), May 05 2003