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%I #10 Jan 28 2014 00:00:48
%S 101101,129921,1837381,127665878878566721,1037998220228997301
%N Palindromic pseudoprimes (base 2).
%C a(6), if it exists, is greater than 2^64. - _Charles R Greathouse IV_, Jun 29 2011
%H Patrick De Geest, <a href="http://www.worldofnumbers.com/won124.htm">Palindromic Pseudoprimes (base 2)</a>
%H Carlos Rivera, <a href="http://www.primepuzzles.net/puzzles/puzz_170.htm">Puzzle 170</a>
%e a(2)= 129921, So the 2nd palindromic pseudoprime(base-2) number is 129921.
%K hard,more,nice,base,nonn
%O 1,1
%A _Shyam Sunder Gupta_, Mar 10 2002; extended Oct 20 2002