OFFSET
1,1
COMMENTS
C. Pomerance proved (private correspondence) that for every n>=1 there exists at least one overpseudoprime (a(n)) for which the multiplicative order of 2 mod a(n) equals 8n+20.
a(25) > 2^64. - Amiram Eldar, Nov 09 2023
LINKS
Vladimir Shevelev, An upper estimate for the overpseudoprime counting function, arXiv:0807.1975 [math.NT], 2008.
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Vladimir Shevelev, Aug 24 2008
EXTENSIONS
a(4) corrected and a(12)-a(24) added by Amiram Eldar, Nov 09 2023
STATUS
approved