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A239789 Primes which are a concatenation of prime(k), prime(k+2) and prime(k+4) for some k.

%I A239789 #11 Mar 29 2014 22:10:58
%S A239789 172331,233141,717989,137149157,191197211,197211227,223229239,
%T A239789 229239251,257269277,331347353,353367379,359373383,467487499,
%U A239789 521541557,617631643,619641647,647659673,677691709,733743757,787809821,797811823,103310491061,106110691091,109711091123
%N A239789 Primes which are a concatenation of prime(k), prime(k+2) and prime(k+4) for some k.
%H A239789 K. D. Bajpai, <a href="/A239789/b239789.txt">Table of n, a(n) for n = 1..3738</a>
%e A239789 172331 is a prime and appears in the sequence because it is the concatenation of prime(7), prime(7+2) and prime(7+4).
%e A239789 233141 is a prime and appears in the sequence because it is the concatenation of prime(9), prime(9+2) and prime(9+4).
%p A239789 with(StringTools): KD := proc() local a,b,d,e; a:=ithprime(n); b:=ithprime(n+2); d:=ithprime(n+4);
%p A239789 e:= parse(cat(a,b,d)); if isprime(e) then RETURN (e); fi; end: seq(KD(), n=1..500);
%t A239789 Select[Table[FromDigits[Flatten[{IntegerDigits[Prime[n]], IntegerDigits[Prime[n+2]], IntegerDigits[Prime[n+4]]}]], {n,1,500}],PrimeQ]
%Y A239789 Cf. A000040, A030461, A030469, A030473, A086040, A086041.
%K A239789 nonn,base
%O A239789 1,1
%A A239789 _K. D. Bajpai_, Mar 26 2014