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%I #18 Feb 22 2018 20:26:51
%S 101107,101113,101149,101173,101197,101281,101293,101347,101359,
%T 101383,101419,101449,101467,101503,101599,101641,101653,101701,
%U 101719,101797,101839,101863,101929,101977,103307,103349,103409,103421,103457,103577
%N Primes n that are concatenation of two 3-digit primes p<q.
%C Or, primes of the form 10^3*p+q, p,q primes, 100<p<q<998.
%C There are exactly 1407 such primes from 101107 to 971977.
%H Andrew Howroyd, <a href="/A168529/b168529.txt">Table of n, a(n) for n = 1..1407</a> (complete sequence)
%t p3=Select[Range[100,999],PrimeQ];Le=Length@p3;Reap[Do[p=10^3*p3[[i]];Do[If[PrimeQ[n=p+p3[[k]]],Sow[n]],{k,i+1,Le}],{i,Le-1}]][[2,1]];
%o (PARI) concat(apply(p->select(n->isprime(n) && isprime(n%1000),[1000*p+p+1..1000*p+997]), select(isprime,[101..996]))) \\ _Andrew Howroyd_, Feb 22 2018
%Y Subsequence of A105184.
%K base,fini,full,nonn
%O 1,1
%A _Zak Seidov_, Nov 28 2009
%E Terms a(25) and beyond in b-file corrected by _Andrew Howroyd_, Feb 22 2018
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