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URL: https://oeis.org/A114249

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A114249
Number of Fermat pseudoprimes to base 7 less than 10^n.
3
1, 2, 6, 16, 73, 234, 659, 1797, 4950, 13070, 33989, 87448
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
KEYWORD
nonn,more
AUTHOR
Eric W. Weisstein, Nov 18 2005
EXTENSIONS
a(9)-a(12) from Hiroaki Yamanouchi, Sep 25 2015
STATUS
approved