cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A160216 Primes congruent to 2^k+1 (mod 2^(k+1)), where k is any odd integer >=1.

Original entry on oeis.org

3, 7, 11, 19, 23, 31, 41, 43, 47, 59, 67, 71, 73, 79, 83, 89, 97, 103, 107, 127, 131, 137, 139, 151, 163, 167, 179, 191, 199, 211, 223, 227, 233, 239, 251, 263, 271, 281, 283, 307, 311, 313, 331, 347, 353, 359, 367, 379, 383, 409, 419, 431, 439, 443, 457, 463
Offset: 1

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Author

Vladimir Shevelev, May 04 2009

Keywords

Comments

Lim_{x -> inf.} the number of terms < x in A160216/A160215 => 2. - Robert G. Wilson v, May 31 2009

Crossrefs

Programs

  • Mathematica
    fQ[n_] := Mod[ Flatten[ FactorInteger[n - 1]] [[2]], 2] == 1; Select[ Prime@ Range@ 90, fQ@# &] (* Robert G. Wilson v, May 31 2009 *)

Formula

{prime(k) : A023506(k) is odd}. - R. J. Mathar, May 08 2009

Extensions

Edited by R. J. Mathar, May 08 2009
More terms from Robert G. Wilson v, May 31 2009