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.

A182288 Primes of form a^2+b^2 such that |a|+|b| is prime of the form 4k+3.

Original entry on oeis.org

5, 29, 37, 61, 73, 101, 181, 193, 241, 269, 277, 293, 349, 409, 521, 541, 593, 661, 701, 929, 937, 1009, 1069, 1109, 1117, 1129, 1217, 1237, 1249, 1289, 1609, 1741, 1753, 1789, 1801, 2029, 2053, 2161, 2221, 2269, 2357, 2389, 2521, 2557, 2609, 2633, 2741, 2753
Offset: 1

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Author

Thomas Ordowski, Apr 23 2012

Keywords

Examples

			The prime 29=5^2+2^2 such that 5+2=7 is prime of form 4k+3.
		

Crossrefs

Cf. A099332.

Programs

  • Mathematica
    nn = 60; t = {}; Do[p1 = a^2 + b^2; p2 = a + b; If[p1 < nn^2 && PrimeQ[p1] && Mod[p2, 4] == 3 && PrimeQ[p2], AppendTo[t, p1]], {a, nn}, {b, a}]; Sort[t] (* T. D. Noe, Apr 23 2012 *)
  • PARI
    list(lim)=my(v=List(),t);for(a=1,sqrt(lim),forstep(b=(2-a)%4+1, min(a,sqrt(lim-a^2)),4,if(isprime(a+b)&&isprime(t=a^2+b^2), listput(v,t)))); vecsort(Vec(v)) \\ Charles R Greathouse IV, Apr 24 2012

Extensions

Extended by T. D. Noe, Apr 23 2012