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A080156 Values of n corresponding to the terms in sequence A080155. For any k, the concatenation of the a(1) to a(k)-th primes is prime and each value of k is the smallest for which this is true.

%I A080156 #8 Apr 12 2014 02:17:39
%S A080156 1,2,5,11,15,50,54,106,148,149,156,188,200,211,248,326,359,374,417,
%T A080156 467,699,798,891,966,1038,1519,1542,1578,1831,1908,1982,2079,2305,
%U A080156 2640,2660,2845,3078,3145,3760,3777,3835,4538,4630,4991,5019,5554,5658,5827
%N A080156 Values of n corresponding to the terms in sequence A080155. For any k, the concatenation of the a(1) to a(k)-th primes is prime and each value of k is the smallest for which this is true.
%H A080156 T. D. Noe, <a href="/A080156/b080156.txt">Table of n, a(n) for n = 1..201</a>
%F A080156 a(n) = prime(A080155(n)).
%p A080156 with(numtheory): pout := [2]: nout := [1]: for n from 2 to 5000 do: p := ithprime(n): d := parse(cat(seq(pout[i],i=1..nops(pout)),p)): if (isprime(d)) then pout := [op(pout),p]: nout := [op(nout),n]: fi: od: nout;
%Y A080156 Cf. A073640, A080152-A080155.
%K A080156 nonn,base
%O A080156 1,2
%A A080156 Mark Hudson (mrmarkhudson(AT)hotmail.com), Jan 31 2003
%E A080156 Edited by _Charles R Greathouse IV_, Apr 30 2010