From the page: “Q: How many Mathematicians does it take to change a lightbulb?
A1: None. It’s left as an exercise for the reader.
A2: In a recent article, Robertson states:
A: One. He gives it to six Californians, thereby reducing the problem to an earlier joke…
However, in earlier work, Wiener [1] has shown that one mathematician can change a lightbulb:
If k mathematicians can change a lightbulb, and if one more simply watches them do it, then k 1 mathematicians will have changed the lightbulb.
It is vacuously true that in a group of 0 mathematicians, any one of them can change a lightbulb. Therefore, by induction, for all n in the positive integers, n mathematicians can change a lightbulb.
Bibliography %u2014
See also : Internet humor[1] Wiener, Matthew P., , Re: YALBJ, 1986″