Mark Hurd
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 Apr8 comment Is “$a + 0i$” in every way equal to just “$a$”? @Farnight In that different context, I agree with you, but no +1 because I disagree with your first sentence in the original context, effectively agreeing with your second sentence :-) Mar13 comment Is there such a thing as proof by example (not counter example) Good answer to the wrong question (IMHO). This should be at Examples of apparent patterns that eventually fail, if it's not mentioned already. Mar10 comment Existence of an holomorphic function Would a proof by contradiction be "easier", i.e. you want $\forall f \exists \psi \forall z: \psi(z+1)=\psi(z)+f(z)$ so attempt $\exists f \forall \psi \exists z: f(z)\neq\psi(z+1)-\psi(z)$. In fact, my first question would be is $\psi(z+1)-\psi(z)$ always holomorphic? Mar3 comment Why are 1 and -1 eigenvalues of this matrix? You do mean the lower right corner of $\mathbf{N}\text{ is }\mathbf{P}^{-1}\begin{bmatrix}1 & && \\ & \ddots && \\ & & 1& \\ &&& -1 \end{bmatrix}\mathbf{P}=\mathbf{P}^{-1}(\mathbf{I}-\begin{bmatrix}0 & && \\ & \ddots && \\ & & 0& \\ &&& 2 \end{bmatrix})\mathbf{P}=\mathbf{I}-2\mathbf{P}^{-1}\begin{bmatrix}0 & && \\ & \ddots && \\ & & 0& \\ &&& 1 \end{bmatrix}\mathbf{P}$? Mar3 comment Exotic bijection from $\mathbb R$ to $\mathbb R$ To cover the domain/range of $\pm(0,1)$, I assume $-\infty6,m$ is likely $<|A_0A_k|$. Oct20 revised How to prove that $\frac{(5m)!(5n)!}{(m!)(n!)(3m+n)!(3n+m)!}$ is a natural number? Slightly further... Sep30 comment Why is Banach–Tarski's paradox so interesting? If you mapped only the irrationals $x\in[0,1]\to x+1$, under certain measures you'd have a mapping from $[0,1] \to [0,2)$, at least, but that's definitely not a finite number of sets. Sep14 awarded Electorate Sep14 revised Is “$a + 0i$” in every way equal to just “$a$”? Someone would have pointed it out by now Sep9 answered How to read this in English?