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A239974 Primes which are a concatenation of prime(k+4), prime(k+2) and prime(k) for some k.

%I A239974 #8 Apr 08 2014 09:14:29
%S A239974 1373,433729,615343,797161,837367,897971,149137127,193181173,
%T A239974 227211197,337317311,367353347,401389379,443433421,557541521,
%U A239974 577569557,587571563,757743733,811797773,823811797,10191009991,10211013997,116311511123,120111871171,130713011291
%N A239974 Primes which are a concatenation of prime(k+4), prime(k+2) and prime(k) for some k.
%C A239974 All the terms in the sequence are primes which are a reverse concatenation of prime(k), prime(k+2) and prime(k+4) for some k.
%H A239974 K. D. Bajpai, <a href="/A239974/b239974.txt">Table of n, a(n) for n = 1..3742</a>
%e A239974 1373 is a prime and appears in the sequence because it is the concatenation of prime(2+4), prime(2+2) and prime(2).
%e A239974 433729 is a prime and appears in the sequence because it is the concatenation of prime(10+4), prime(10+2) and prime(10).
%p A239974 with(StringTools): KD := proc() local a, b, d, e; a:=ithprime(n+4); b:=ithprime(n+2); d:=ithprime(n);  e:= parse(cat(a, b, d)); if isprime(e) then RETURN (e); fi; end: seq(KD(), n=1..500);
%t A239974 Select[Table[FromDigits[Flatten[{IntegerDigits[Prime[n+4]],IntegerDigits[Prime[n+2]], IntegerDigits[Prime[n]]}]], {n,1,500}], PrimeQ]
%Y A239974 Cf. A000040, A030461, A030469, A030473, A086040, A086041, A239789.
%K A239974 nonn,base
%O A239974 1,1
%A A239974 _K. D. Bajpai_, Mar 30 2014