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 A102109 Smallest prime a(n) such that concatenation of first n+1 primes starting from a(n), separated by n zeros, is prime. 0
 23, 79, 41, 53, 163, 283, 307, 151, 101, 199, 367, 149, 2027, 1783, 1621, 2999, 5303, 2699, 2381, 7129, 3019, 4159, 2503, 41647, 2971, 9413, 8369, 5801, 7247, 18517, 15887, 9293, 2699, 4211, 157, 3821 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS EXAMPLE a(5)=163: 1630000016700000173000001790000018100000191 is prime. PROG (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 CROSSREFS Sequence in context: A267821 A237987 A157270 * A238677 A302281 A141974 Adjacent sequences:  A102106 A102107 A102108 * A102110 A102111 A102112 KEYWORD base,nonn,less AUTHOR Ray G. Opao, Feb 14 2005 EXTENSIONS More terms from David Wasserman, Apr 04 2008 Extended by D. S. McNeil, Dec 05 2010 STATUS approved

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Last modified October 22 01:46 EDT 2020. Contains 337948 sequences. (Running on oeis4.)