Wilson's Theorem in Disguise
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The American Mathematical Monthly problem 10578 considers a sequence defined by recurrence equation with initial conditions
and asks to show that
is only an integer for prime
.
Contributed by: Oleksandr Pavlyk and Brett Champion (March 2011)
Open content licensed under CC BY-NC-SA
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It is easy to find a symbolic solution of the above recurrence equation:
The above fraction is an integer only for prime by virtue of Wilson's theorem.
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