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%I #10 Jun 19 2014 11:50:16
%S 4173310657,97158322307,137221330559,223341346447,251390752919,
%T 271423157191,367552173973,433647386371,487729796581,491741197813,
%U 5097643101281,6018831116447,6179109119983,6439439124577,70910343136379,71910459137477,82311933155327,82912109157739
%N Primes which are concatenation of prime(n), prime(10n) and prime(100n).
%H K. D. Bajpai, <a href="/A244064/b244064.txt">Table of n, a(n) for n = 1..11139</a>
%e 4173310657 is in the sequence because concatenation of [prime(13), prime(130), prime(1300)] = 4173310657, which is a prime.
%e 97158322307 is in the sequence because concatenation of [prime(25), prime(250), prime(2500)] = 97158322307, which is a prime.
%p with(numtheory): with(StringTools): A244064:= proc() local a,b,c,m; a:=ithprime(n); b:=ithprime(10*n); c:=ithprime(100*n);m:=parse(cat(a,b,c)); if isprime(m) then RETURN (m); fi; end: seq(A244064 (), n=1..300);
%t A244064 = {}; Do[t = FromDigits[Flatten[IntegerDigits /@ {Prime[n], Prime[10 n], Prime[100 n]}]]; If[PrimeQ[t], AppendTo[A244064, t]], {n, 300}]; A244064
%Y Cf. A000040, A030469.
%Y Cf. A031343 (prime(10n)), A031921 (prime(100n)).
%K nonn,base
%O 1,1
%A _K. D. Bajpai_, Jun 19 2014