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A294135
Sorted list of prime factors of numbers of the form 9^(2^m) + 2^(2^m) with m >= 0.
5
5, 11, 17, 257, 449, 1601, 6577, 20353, 25601, 40961, 65537, 95873, 163841, 176129, 1179649, 8452097, 13631489, 26419201, 32310529, 38031361, 56867009, 59637761, 144310273, 480865793, 697434113, 1572864001, 2013265921, 7547650049, 62872289281, 483049603073
OFFSET
1,1
COMMENTS
Primes p other than 7 such that the multiplicative order of 9/2 (mod p) is a power of 2.
LINKS
Arkadiusz Wesolowski, Table of n, a(n) for n = 1..43
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.
PROG
(PARI) print1(5, ", "11, ", "); forprime(p=17, 483049603073, z=znorder(Mod(9/2, p)); if(2^ispower(z)==z, print1(p, ", ")));
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved