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.

A191019 Rational primes that decompose in the quadratic field Q(sqrt(-19)).

Original entry on oeis.org

5, 7, 11, 17, 23, 43, 47, 61, 73, 83, 101, 131, 137, 139, 149, 157, 163, 191, 197, 199, 229, 233, 239, 251, 263, 271, 277, 283, 311, 313, 347, 349, 353, 359, 367, 389, 397, 419, 443, 457, 461, 463, 467, 479, 491, 499, 503, 541, 557, 571, 577, 587, 593, 613
Offset: 1

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Author

T. D. Noe, May 24 2011

Keywords

Comments

Primes which are 1, 5, 7, 9, 11, 17, 23, 25, or 35 mod 38. - Charles R Greathouse IV, Mar 18 2018

Programs

  • Magma
    [p: p in PrimesUpTo(613) | IsOne(JacobiSymbol(p, 19))]; // Bruno Berselli, Sep 10 2012
    
  • Mathematica
    Select[Prime[Range[200]], JacobiSymbol[#,19]==1&]
  • PARI
    list(lim)=my(v=List()); forprime(p=5,lim, if(kronecker(-19,p)==1, listput(v,p))); Vec(v) \\ Charles R Greathouse IV, Mar 18 2018

Formula

a(n) ~ 2n log n. - Charles R Greathouse IV, Mar 18 2018

Extensions

Definition corrected by N. J. A. Sloane, Dec 25 2017