Strongly recommended the free excellent MIT Math for high school, undergrads/grads and any self-study Math learners.

Thanks Prof. Gilbert Strang for the unselfish sharing.

http://ocw.mit.edu/faculty/gilbert-strang/

I find extreme pleasure when I discovered his brilliant lecture notes in “Generating Function” – a Discrete Math technique for computing Sequence using function, and the application in complex Combinatorics. Download PDF here.

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