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.

A135386 Mersenne composites A065341 with 4 or more prime factors.

Original entry on oeis.org

10384593717069655257060992658440191, 2854495385411919762116571938898990272765493247, 182687704666362864775460604089535377456991567871
Offset: 1

Views

Author

Artur Jasinski, Dec 09 2007

Keywords

Crossrefs

Programs

  • Maple
    A135386 := proc(n) local i;
    i := 2^(ithprime(n))-1:
    if (nops(numtheory[factorset](i)) > 3) then
       RETURN (i)
    fi: end: seq(A135386(n), n=1..37); # Jani Melik, Feb 09 2011
  • Mathematica
    k = {}; Do[If[ ! PrimeQ[2^Prime[n] - 1], c = FactorInteger[2^Prime[n] - 1]; d = Length[c]; If[d >3, AppendTo[k, 2^Prime[n] - 1]]], {n, 1, 40}]; k