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%I #13 Jan 22 2021 13:57:17
%S 23,79,41,53,163,283,307,151,101,199,367,149,2027,1783,1621,2999,5303,
%T 2699,2381,7129,3019,4159,2503,41647,2971,9413,8369,5801,7247,18517,
%U 15887,9293,2699,4211,157,3821
%N Smallest prime a(n) such that concatenation of first n+1 primes starting from a(n), separated by n zeros, is prime.
%e a(5)=163: 1630000016700000173000001790000018100000191 is prime.
%o (PARI) {for(n=1,99, my(p, z=concat(vector(n,k,"0")), v=vector(n+1,k,Str(z,p=prime(k)))); while(!ispseudoprime(eval(concat(v))), v=concat([vecextract(v,"^1"),[Str(z,p=nextprime(p+1))]])); print1(eval(v[1])","))} \\ _M. F. Hasler_, Dec 05 2010
%K base,nonn,less
%O 1,1
%A _Ray G. Opao_, Feb 14 2005
%E More terms from _David Wasserman_, Apr 04 2008
%E Extended by _D. S. McNeil_, Dec 05 2010
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