%I
%S 5,11,17,31,41,89,229,239,263,307,313,317,353,359,383,389,401,409,439,
%T 449,563,619,701,761,773,787,797,827,907,929,1061,1163,1409,1447,1579,
%U 1597,1619,1621,1637,1697,1877,1933,2011,2029,2129,2131
%N Primes which when concatenated with next two primes are also prime.
%H Paolo P. Lava, <a href="/A030468/b030468.txt">Table of n, a(n) for n = 1..2500</a>
%e concat(5, 7, 11) = 5711 is prime.  _Paolo P. Lava_, Jan 25 2017
%p with(numtheory): P:=proc(q) local a,b,c,d,n;for n from 1 to q do a:=ithprime(n); b:=nextprime(a); c:=nextprime(b); d:=b*10^(ilog10(c)+1)+c;
%p if isprime(a*10^(ilog10(d)+1)+d) then a; fi;
%p od; end: seq(P(k),k=1..400); # _Paolo P. Lava_, Jan 25 2017
%Y Cf. A000040.
%K nonn,base
%O 1,1
%A _Patrick De Geest_
