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His (co-authored) book "A=B" is also very good.
His (co-authored) book "A=B" is also very good.
It's also available online for free: http://www.math.upenn.edu/~wilf/AeqB.html http://www.math.upenn.edu/~wilf/AeqB.html
Yes, it is closely related to the topic of this essay, i.e. automating certain parts of mathematics.