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A comment on A regular expression to check for prime numbers. Parent comment

Re:A regular expression to check for prime numbers by maemilius on Thursday February 12, 2015 @05:34PM (#9041833)
If I may suggest an improvement:

  function isPrime(n) {
    var re = /^1?$|^(11+?)\1+$/,
          s = (new Array(n+1)).join('1');
  
    return !re.test(s);
  }
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Re:A regular expression to check for prime numbers by myfonj on Thursday February 12, 2015 @06:23PM (#9042027)
Why not just function isPrime(n) { return !/^1?$|^(11+?)\1+$/.test(Array(n+1).join('1')) } then? :]
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Re:A regular expression to check for prime numbers by quadratini on Thursday February 12, 2015 @06:04PM (#9041941)
es6: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Refe...
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Re:A regular expression to check for prime numbers by _lce0 on Thursday February 12, 2015 @05:44PM (#9041867)
man that's genius!!
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