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A123933 a(n) = smallest positive composite integer such that a(n)-10^k is prime for all k=1,2..n. 0
12, 111, 1007, 10109, 100709, 1008819, 10326309, 106635053 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

a(n)=0 (mod 7)for n>6

EXAMPLE

a(3)=1007 is included as 997, 907 and 7 are primes.

CROSSREFS

Sequence in context: A066042 A153597 A036733 * A199691 A077754 A199357

Adjacent sequences:  A123930 A123931 A123932 * A123934 A123935 A123936

KEYWORD

hard,nonn

AUTHOR

Anton Vrba (antonvrba(AT)yahoo.com), Nov 29 2006

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Last modified February 17 09:15 EST 2012. Contains 206009 sequences.