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Last active May 12, 2016 17:35
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Factorial problem
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Factorial.md

Problem statement

x! = (7!)! / 7!  # solve for x

Solution

Let 7! be N. Re-express as

x! = N! / N

that's the same as

x! = (N - 1)!

so

x  = (N - 1)

ergo

x = 7! - 1

which is

5039
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