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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; text; internal format)
OFFSET
1,1
COMMENTS
If A(x) is the counting function of the terms not exceeding x, then A(x) grows similarly to Pi(x)/3, see A000720.
Lim_{x -> inf.} the number of terms < x in A160216/A160215 => 2. - Robert G. Wilson v, May 31 2009
LINKS
FORMULA
{prime(k) : A023506(k) is even}. - R. J. Mathar, May 08 2009
MATHEMATICA
fQ[n_] := Mod[ Flatten[ FactorInteger[n - 1]] [[2]], 2] == 0; Select[ Prime@ Range@ 155, fQ@# &] (* Robert G. Wilson v, May 31 2009 *)
CROSSREFS
Cf. A000040.
Sequence in context: A291275 A291278 A177349 * A068486 A099332 A279687
KEYWORD
nonn
AUTHOR
Vladimir Shevelev, May 04 2009
EXTENSIONS
Edited by R. J. Mathar, May 08 2009
More terms from Robert G. Wilson v, May 31 2009
STATUS
approved

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Last modified March 19 04:58 EDT 2024. Contains 370952 sequences. (Running on oeis4.)