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%I #4 Feb 15 2011 12:26:18
%S 112121,113131,115151,119191,127271,131311,134341,136361,140401,
%T 142421,145451,149491,157571,158581,161611,169691,170701,172721,
%U 178781,182821,187871,190901,191911,196961,197971,1100010001,1100210021,1101710171
%N Primes of the concatenated form 1nn1 where n is an integer >=0.
%e 112121 is prime and is of the form 1nn1 for n=12.
%e 1100010001 is prime and is of the form 1nn1 for n=1000.
%Y Cf. A100846; A100496 for the values of n that produce these primes.
%K easy,nonn,base
%O 1,1
%A Mark Hudson (mrmarkhudson(AT)hotmail.com), Jan 12 2005