OFFSET
1,1
COMMENTS
All prime divisors of (2Q)^8 + 1 are congruent to 1 modulo 16.
REFERENCES
G. A. Jones and J. M. Jones, Elementary Number Theory, Springer-Verlag, NY, (1998), p. 271.
EXAMPLE
a(3) = 5136468762577 is the smallest prime divisor of (2Q)^8 + 1 = 45820731194492299767895461612240999140120699535617 = 5136468762577 * 33000748370307713 * 270317134666005456817, where Q = 17 * 47441.
MATHEMATICA
a = {17}; q = 1;
For[n = 2, n <= 3, n++,
q = q*Last[a];
AppendTo[a, Min[Select[FactorInteger[(2*q)^8 + 1][[All, 1]],
Mod[#, 16] == 1 &]]];
];
a (* Robert Price, Jul 14 2015 *)
CROSSREFS
KEYWORD
more,nonn
AUTHOR
Nick Hobson, Nov 18 2006
EXTENSIONS
a(5)-a(10) from Max Alekseyev, Oct 18 2008
STATUS
approved