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.

A222424 Numbers n such that n and n + 14 are prime and there is a power of two in the interval (n,n+14).

Original entry on oeis.org

3, 5, 23, 29, 53, 59, 509, 1019, 2039, 262133, 262139, 536870909, 73786976294838206459, 2787593149816327892691964784081045188247543
Offset: 1

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Author

Brad Clardy, Feb 24 2013

Keywords

Comments

It is a conjecture that this is a finite sequence. A search was conducted out to 2^1500.

Crossrefs

Programs

  • Magma
    //Program finds primes separated by an even number (called gap) which
    //have a power of two between them. Program starts with the smallest
    //power of two above gap. Primes less than this starting point can be
    //checked by inspection.
    gap:=14;
    start:=Ilog2(gap)+1;
    for i:= start to 1000 do
        powerof2:=2^i;
        for k:=powerof2-gap+1 to powerof2-1 by 2 do
            if (IsPrime(k) and IsPrime(k+gap)) then k;
            end if;
        end for;
    end for;