Just Four Fun

Here's an interesting quickie:

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"Map a number to the number of letters in its name

20 (twenty) --> 6 (six) --> 3 (three) --> 5 (five) --> four (4) --> four(4) --> ...

It turns out that ANY number eventually goes to 4"

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I took this verbatim from Bill Gasarch's post today (his third installment reviewing the last Gathering For Gardner get-together).

When one stops to think about it, probably not all that unusual (just requiring a lower integer with the same number of letters as that integer, and a second larger or smaller integer involving that same number of letters). So how many other major languages have this, or a similar, pattern?