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problem of four n’s
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Why Do Some Cicadas Appear Only Every 17 Years?

problem of four n’s

Learn about this topic in these articles:

major reference

  • See an explanation on Zeno's Achilles paradox, an infinite series concept used in finance to pay off mortgages
    In number game: Digital problems

    The problem of the four n’s calls for the expression of as large a sequence of integers as possible, beginning with 1, representing each integer in turn by a given digit used exactly four times. The answer depends upon the rules of operation that are admitted.…

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