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A160215 Primes congruent to 2^k+1 (mod 2^(k+1)), where k is any even integer >=0. 3
2, 5, 13, 17, 29, 37, 53, 61, 101, 109, 113, 149, 157, 173, 181, 193, 197, 229, 241, 257, 269, 277, 293, 317, 337, 349, 373, 389, 397, 401, 421, 433, 449, 461, 509, 541, 557, 577, 593, 613, 653, 661, 677, 701, 709, 733, 757, 769, 773, 797, 821, 829, 853, 877 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

If A(x) is the counting function of the terms not exceeding x, then A(x) grows similar to pi(x)/3, see A000720.

The Lim (x -> inf.) the number of terms < x in A160216/A160215 => 2. [From Robert G. Wilson v (rgwv(AT)rgwv.com), May 31 2009]

FORMULA

A000040 \ A160216.

{prime(k) : A023506(k) is even} - [R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Mary 08 2009]

MATHEMATICA

fQ[n_] := Mod[ Flatten[ FactorInteger[n - 1]] [[2]], 2] == 0; Select[ Prime@ Range@ 155, fQ@# &] [From Robert G. Wilson v (rgwv(AT)rgwv.com), May 31 2009]

CROSSREFS

A000040

Sequence in context: A086807 A002313 A177349 * A068486 A099332 A031439

Adjacent sequences:  A160212 A160213 A160214 * A160216 A160217 A160218

KEYWORD

nonn

AUTHOR

Vladimir Shevelev (shevelev(AT)bgu.ac.il), May 04 2009

EXTENSIONS

Edited by R. J. Mathar (mathar(AT)strw.leidenuniv.nl), May 08 2009

More terms from Robert G. Wilson v (rgwv(AT)rgwv.com), May 31 2009

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Last modified February 15 10:06 EST 2012. Contains 205763 sequences.