S Huntsman
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 Jan4 awarded Autobiographer Dec15 awarded Caucus Jul30 comment Why is the volume of a sphere $\frac{4}{3}\pi r^3$? The negative solution to Hilbert's third problem (en.wikipedia.org/wiki/Hilbert%27s_third_problem) strongly suggests (if not shows outright) that this and related questions require calculus in an essential way, and that calculus-free "derivations" are just hiding something. Jul2 awarded Curious Apr29 comment Meaning of pullback Consider $f = g \circ \alpha$. The universal property implies that the corresponding pullback satisfies (using Wikipedia notation current at the time of writing) $P = \text{dom } \alpha$, $p_1 = id$, $p_2 = \alpha$, so that $\alpha$ is the pullback of $f = g \circ \alpha$ along $\alpha$. Jan22 comment How can I explicitly construct a *nice* conformal mapping from a triangle to a square in MATLAB? Jan22 comment How can I explicitly construct a *nice* conformal mapping from a triangle to a square in MATLAB? @Arkamis--Look at the polygon p1. The stuff you're preoccupied with doesn't have anything to do with the actual polygon, just an easy way to generate points inside it. Jan22 comment How can I explicitly construct a *nice* conformal mapping from a triangle to a square in MATLAB? I should also note that I've seen mathfaculty.fullerton.edu/mathews/c2003/… and this (or similar maps) doesn't really solve my problem AFAIK. Jan22 comment How can I explicitly construct a *nice* conformal mapping from a triangle to a square in MATLAB? @Arkamis--I don't think so. That's just the y-limits of the equilateral triangle, which is centered at the origin. Jan22 asked How can I explicitly construct a *nice* conformal mapping from a triangle to a square in MATLAB? Aug31 accepted Reference request for Euclidean metric in hyperspherical coordinates Aug31 asked Reference request for Euclidean metric in hyperspherical coordinates Jul26 comment Number of item distributions in buckets of different sizes @VladimirDotsenko: I wish I could have read your comment back in 2001! Jul26 comment Number of item distributions in buckets of different sizes I would hope that this is not closed: if there is a simple answer, I am not aware of it and would like to know it. I previously wondered about this very question many years ago and based on that experience I do not think it should be migrated. For instance, I could not figure out how to make the straightforward appeal to inclusion-exclusion actually work in practice. Jul26 comment Number of item distributions in buckets of different sizes The case where $c_b \ge I$ gives $\binom{I+B-1}{I}$, by "stars and bars": en.wikipedia.org/wiki/Stars_and_bars_(combinatorics) Dec8 accepted What discrete memoryless channels have zero capacity? Dec6 comment What discrete memoryless channels have zero capacity? Edited to remove the question's ambiguity. Dec6 revised What discrete memoryless channels have zero capacity? added 29 characters in body Nov30 asked What discrete memoryless channels have zero capacity? Sep14 accepted Boolean circuits and digraphs