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%I #21 Feb 08 2021 16:29:20
%S 3,13,37,9901,333667,99990001,999999000001,9999999900000001,
%T 13168164561429877,130654897808007778425046117
%N Primes p such that p^2 divides p.p.p where dot "." means concatenation.
%C Primes p dividing 10^(2*d)+10^d+1 where d=ceiling(log(p)/log(10)) is the number of decimal digits in p. - _Max Alekseyev_
%C a(11) > 10^156. - _Max Alekseyev_, Feb 08 2021
%C There is no prime p such that p^2 divides p.p.
%C All primes of the forms 10^(2m) - 10^m + 1 or (1/3)*(10^(2m) + 10^m + 1) are in the sequence.
%C Primes in A243162. - _Hans Havermann_, May 31 2014
%Y Cf. A147553, A243162.
%K nonn,base,more
%O 1,1
%A _Farideh Firoozbakht_, Dec 26 2008
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