%I A057957
%S A057957 1,2,3,3,3,5,3,4,6,6,4,7,3,6,7,5,3,10,3,8,8,7,4,10,7,7,9,8,6,13,3,7,9,
%T A057957 7,9,14,5,7,8,10,5,14,5,10,13,9,6,13,5,14,11,10,6,15,12,11,9,9,6,17,3,
%U A057957 8,14,9,9,15,5,11,9,16,6,19,6,10,14,11,10,18,5,13,16,10,8,19,7,10,11
%N A057957 Number of prime factors of 4^n - 1 (counted with multiplicity).
%H A057957 S. S. Wagstaff, Jr., <a href="http://www.cerias.purdue.edu/homes/ssw/
               cun/main600">Main Tables</a> from the Cunningham Project.
%H A057957 S. S. Wagstaff, Jr., <a href="http://www.cerias.purdue.edu/homes/ssw/
               cun/index.html">The Cunningham Project</a>
%F A057957 Mobius transform of A085029 - T. D. Noe (noe(AT)sspectra.com), Jun 19 
               2003
%Y A057957 Cf. A057951-A057958, A046051.
%Y A057957 Cf. A085029.
%Y A057957 Sequence in context: A103359 A020481 A066660 this_sequence A076559 A102601 
               A092308
%Y A057957 Adjacent sequences: A057954 A057955 A057956 this_sequence A057958 A057959 
               A057960
%K A057957 nonn
%O A057957 1,2
%A A057957 Patrick De Geest (pdg(AT)worldofnumbers.com), Nov 15 2000.