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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

Table of n, a(n) for n=1..36.

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.)