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Homework Help: Ulam #'s and calculator!

  1. Nov 14, 2005 #1
    What are Ulam #'s? A ulam #, if an only if it can be written uniquely as the sumof two distinct Ulam #'s. ???

    I need to make a list of the firts 20 Ulam #'s. I got the first 8. It's there any formanula or something easy to do it?

    How many Ulam number are thre? Prove answer


    Write a program that will generate all Ulam #'s less than a given number n. Use your progam to find all the Ulam numbers less than 1000. I am not good with calculator plus I don't have manual, I have a TI-83.:confused:

    How many are there? ???

    What portion of these are prime? Prime is a number divisible by one and by itself only... right?
  2. jcsd
  3. Nov 14, 2005 #2


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