Prime solver giving composite numbers











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primes=[2]
a=3
b=1
while True:
try:
if a%primes[b]==0:
a+=2
else:
b+=1
except IndexError:
primes.append(a)
print a
a+=2
b=1


I try to run this code to give me a list of primes, but it keeps spitting out numbers like 27,95, and other, larger composite numbers. The code runs and there are no syntax errors preventing it from doing so, but it will give me incorrect values, and I don't know why. Please let me know if you find any errors or if it is a problem with Python3.









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    up vote
    0
    down vote

    favorite












    primes=[2]
    a=3
    b=1
    while True:
    try:
    if a%primes[b]==0:
    a+=2
    else:
    b+=1
    except IndexError:
    primes.append(a)
    print a
    a+=2
    b=1


    I try to run this code to give me a list of primes, but it keeps spitting out numbers like 27,95, and other, larger composite numbers. The code runs and there are no syntax errors preventing it from doing so, but it will give me incorrect values, and I don't know why. Please let me know if you find any errors or if it is a problem with Python3.









    share







    New contributor




    Connor Sponsler is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
    Check out our Code of Conduct.






















      up vote
      0
      down vote

      favorite









      up vote
      0
      down vote

      favorite











      primes=[2]
      a=3
      b=1
      while True:
      try:
      if a%primes[b]==0:
      a+=2
      else:
      b+=1
      except IndexError:
      primes.append(a)
      print a
      a+=2
      b=1


      I try to run this code to give me a list of primes, but it keeps spitting out numbers like 27,95, and other, larger composite numbers. The code runs and there are no syntax errors preventing it from doing so, but it will give me incorrect values, and I don't know why. Please let me know if you find any errors or if it is a problem with Python3.









      share







      New contributor




      Connor Sponsler is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.











      primes=[2]
      a=3
      b=1
      while True:
      try:
      if a%primes[b]==0:
      a+=2
      else:
      b+=1
      except IndexError:
      primes.append(a)
      print a
      a+=2
      b=1


      I try to run this code to give me a list of primes, but it keeps spitting out numbers like 27,95, and other, larger composite numbers. The code runs and there are no syntax errors preventing it from doing so, but it will give me incorrect values, and I don't know why. Please let me know if you find any errors or if it is a problem with Python3.







      python security primes mathematics





      share







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      Connor Sponsler is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.










      share







      New contributor




      Connor Sponsler is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.








      share



      share






      New contributor




      Connor Sponsler is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.









      asked 7 mins ago









      Connor Sponsler

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      New contributor




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      Check out our Code of Conduct.





      New contributor





      Connor Sponsler is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.






      Connor Sponsler is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.



























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