Let's say you have a digit function, D(n), which equals the number of digits in the input (n). (e.g., 19 becomes 2, 142151 become 6...well, you see)(adsbygoogle = window.adsbygoogle || []).push({});

(where n!! is, well, a factorial of a factorial)

1) Now when will D(n!!) become a googol? A googolplex?

2) Now when will D(D(n!!)) become a googol? A googolplex?

3) In subjective but ""somewhat"" reasonable language, how fast do you think the sequence S(n)=D(n!)-n increases? (slow..med..fast...whichever way to describe it)

(For easy calculation of digits, just set your graphing calculator to "Scientific" exponential format in the MODE screen)

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# Digit-Factorial question

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