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A171655 Numbers n such that 10^n*(7+3*10^n)+3 is prime. 0
0, 1, 2, 3, 7, 20, 22, 65, 122, 355, 561, 2216, 5638, 7271 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,3
COMMENTS
Values corresponding to n=5638 and n=7271 were both certified Fermat and Lucas PRPs with WinPFGW and submitted to Lifchitz's Top PRPs database.
LINKS
PROG
(PARI) is(n)=ispseudoprime(10^n*(7+3*10^n)+3) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
Sequence in context: A110498 A244917 A172976 * A293683 A006073 A052402
KEYWORD
more,nonn
AUTHOR
Jason Earls, Dec 14 2009
STATUS
approved

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Last modified April 19 16:52 EDT 2024. Contains 371794 sequences. (Running on oeis4.)