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A163184 Primes of the form 8k + 1 dividing 2^j + 1 for some odd j. 1
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 (list; graph; refs; listen; history; text; internal format)
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

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Last modified April 10 22:19 EDT 2021. Contains 342856 sequences. (Running on oeis4.)