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A110285 Numbers n such that n*10^n + n - 1 is prime. 0
168, 760, 2154, 9172 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Not proved, only Fermat and Lucas PRPs. Next term is greater than 12000. Concerning primes of the form n * 10^n + n + 1, only n=42 yields one for all n up to 7700.

LINKS

Table of n, a(n) for n=1..4.

CROSSREFS

Sequence in context: A234823 A234816 A245868 * A235071 A235064 A070835

Adjacent sequences:  A110282 A110283 A110284 * A110286 A110287 A110288

KEYWORD

more,nonn

AUTHOR

Jason Earls (zevi_35711(AT)yahoo.com), Sep 07 2005

STATUS

approved

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Last modified October 22 21:52 EDT 2014. Contains 248411 sequences.