OFFSET
1,1
COMMENTS
Number k from A002253 is a term iff 10 is a cubic residue modulo prime p = 3*2^k + 1, that is, 10^(2^k) == 1 (mod p). - Max Alekseyev, Sep 06 2025
REFERENCES
Wilfrid Keller, private communication, 2008.
LINKS
Anders Björn and Hans Riesel, Factors of generalized Fermat numbers, Math. Comp. 67 (1998), no. 221, pp. 441-446.
Anders Björn and Hans Riesel, Table errata to “Factors of generalized Fermat numbers”, Math. Comp. 74 (2005), no. 252, p. 2099.
Anders Björn and Hans Riesel, Table errata 2 to "Factors of generalized Fermat numbers", Math. Comp. 80 (2011), pp. 1865-1866.
C. K. Caldwell, Top Twenty page, Generalized Fermat Divisors (base=10)
OEIS Wiki, Generalized Fermat numbers
CROSSREFS
KEYWORD
nonn,hard,more
AUTHOR
Arkadiusz Wesolowski, Feb 10 2016
STATUS
approved
