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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.

A052230 Primes p from A031924 such that A052180(primepi(p)) = 5.

Original entry on oeis.org

23, 31, 53, 61, 83, 151, 173, 233, 263, 271, 331, 353, 383, 443, 503, 541, 563, 571, 593, 601, 653, 751, 991, 1013, 1103, 1223, 1231, 1283, 1291, 1321, 1433, 1493, 1553, 1613, 1621, 1741, 1861, 1973, 2011, 2063, 2131, 2281, 2333, 2341, 2371, 2393, 2543
Offset: 1

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Author

Labos Elemer, Feb 01 2000

Keywords

Crossrefs

Programs

  • Maple
    filter:= proc(p) local t,m,flag;
      flag:= false;
      for t from p+1 to p+5 do
        m:= min(numtheory:-factorset(t));
        if m > 5 then return false
        elif m = 5 then flag:= true
        fi
      od;
      flag
    end proc:
    Res:= NULL: count:= 0:
    q:= 1: p:= 2:
    while count < 100 do
      q:= p;
      p:= nextprime(p);
      if p-q = 6 and filter(q) then
        count:= count+1; Res:= Res, q;
      fi
    od:
    Res; # Robert Israel, Aug 12 2018