Recent content by Evil Robot

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    Basic invertible matrix theorem proof.

    If A and B are invertible matrices, can anyone prove that (AB)^(-1) = B^(-1)*A^(-1) ? This is not exactly the problem, I have, but my group theory problem is isomorphic to it :).
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    Undergrad Math geniuses: Design a function that gives this output

    What is the dustbin packing algorithm? Is it polynomial in nature? What are the best algorithms for prime factoring? Are they polynomial (guessing no here)?
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    Undergrad Math geniuses: Design a function that gives this output

    Yep, I noted that in my post :).
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    Undergrad Math geniuses: Design a function that gives this output

    The other angle of attack I could think of is recursive, with the base case having two cases: Case 1: Being one integer: n. Case 2: Given: a positive integer n Return: two positive integers {a,b} such that a*b=n, the variance of {a,b} is minimized, and a>=b. The return might also be...
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    Undergrad Math geniuses: Design a function that gives this output

    No, it's not homework. I've managed to reduce it to a problem of combinatorially grouping the prime factors of an integer, but more than that is beyond me (i.e. minimizing the difference between the factors chosen and the cube root of the number)
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    Undergrad Math geniuses: Design a function that gives this output

    A general algorithm works too. Given: a positive integer n Return: three positive integers {a,b,c} such that a*b*c=n, the variance of {a,b,c} is minimized, and a>=b>=c. The return might also be understood as "give the (integer) dimensions of the cubiest cuboid of volume n". I suspect...