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%I #7 Jun 12 2014 20:15:08
%S 3,5,7,7,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,
%T 11,11,11,11,11,11,11,11,11,11,101,101,101,101,101,101,101,101,101,
%U 131,131,131,131,131,131,131,151,151,151,151,151,151,151,151,181,181,181
%N Largest palindromic prime < n-th-semiprime.
%t With[{nn=150},Module[{palpr=Reverse[Select[Prime[Range[nn]],IntegerDigits[ #] == Reverse[ IntegerDigits[#]]&]],semis = Select[Range[2nn],PrimeOmega[ #] == 2&]},Flatten[Table[Select[palpr,#<semis[[n]]&,1],{n,Length[ semis]}]]]] (* _Harvey P. Dale_, Jun 12 2014 *)
%K base,easy,nonn
%O 1,1
%A _Giovanni Teofilatto_, Sep 08 2010
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