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How big are factorials?

99 points · 43 comments · ibobev

  1. cwmoore · · focus · HN ↗
    I came across an interesting feature of factorials while making the puzzle books at <a href="https:&#x2F;&#x2F;www.kakurokokoro.com" rel="nofollow">https:&#x2F;&#x2F;www.kakurokokoro.com

    The widest two rows are nine digits across, but while the first can be any of arrangements of the digits 1-9, the second cannot repeat any digits in the same columns, and so it limits allowable permutations to the number of derangements — which is close to 9!&#x2F;e (where e is Euler’s Constant 2.718…)

    No idea what this has to do with the relationship of i and pi.

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