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A114247 Number of Fermat pseudoprimes to base 5 less than 10^n. 6
1, 1, 5, 20, 73, 248, 745, 1954, 5239, 13837, 36042, 92893 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,3
LINKS
Eric Weisstein's World of Mathematics, Fermat Pseudoprime
MATHEMATICA
Table[Count[Select[Range[2, 10^6], ! PrimeQ[#] && PowerMod[5, # - 1, #] == 1 &], x_ /; x < 10^n], {n, 6}] (* Robert Price, Jun 09 2019 *)
CROSSREFS
Sequence in context: A270080 A271136 A118049 * A272086 A006650 A034535
KEYWORD
nonn,more
AUTHOR
Eric W. Weisstein, Nov 18 2005
EXTENSIONS
a(9)-a(12) from Hiroaki Yamanouchi, Sep 25 2015
STATUS
approved

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Last modified March 28 16:34 EDT 2024. Contains 371254 sequences. (Running on oeis4.)