A163184 Primes of the form 8k + 1 dividing 2^j + 1 for some odd j.

281, 617, 1033, 1049, 1097, 1193, 1481, 1553, 1753, 1777, 2281, 2393, 2473, 2657, 2833, 2857, 3049, 3529, 3673, 3833, 4049, 4153, 4217, 4273, 4457, 4937, 5113, 5297, 5881, 6121, 6449, 6481, 6521, 6529, 6569, 6761, 6793, 6841, 7121, 7129, 7481, 7577, 7817, 8081, 8233, 8537, 9001, 9137, 9209, 9241

Offset

1,1

Comments

Each term p has the form 2^r*j + 1, where r >= 3, j is odd, and ord_p(-2) divides j.

Links

Table of n, a(n) for n=1..50.

Example

281 is in the sequence as 281 = 2^3*35 + 1 and 281 | 2^35 + 1.

Maple

with(numtheory):A:=NULL:p:=2: for c to 500 do p:=nextprime(p); if order(-2, p) mod 2=1 and p mod 8 = 1 then A:=A, p;; fi; od:A;

Crossrefs

Set difference of A163183 and A007520.

Subsequence of A033203, A051071, A051073, A051077, A051085, A051101.

Sequence in context: A056215 A142397 A142546 * A122710 A161191 A108836

Adjacent sequences: A163181 A163182 A163183 * A163185 A163186 A163187

Keyword

easy,nonn

Author

Christopher J. Smyth, Jul 22 2009

Extensions

More terms from Max Alekseyev, Sep 29 2016

Status

approved