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A114249 Number of Fermat pseudoprimes to base 7 less than 10^n. 2
1, 2, 6, 16, 73, 234, 659, 1797, 4950, 13070, 33989, 87448 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
LINKS
Eric Weisstein's World of Mathematics, Fermat Pseudoprime
MATHEMATICA
Table[Count[Select[Range[2, 10^6], ! PrimeQ[#] && PowerMod[7, # - 1, #] == 1 &], x_ /; x < 10^n], {n, 6}] (* Robert Price, Jun 09 2019 *)
CROSSREFS
Sequence in context: A009328 A009346 A009367 * A147910 A147902 A147893
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 June 13 22:21 EDT 2024. Contains 373391 sequences. (Running on oeis4.)