Old John
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 1d awarded Good Answer Apr 28 comment Expressing $2002^{2002}$ as a sum of cubes The very last sentence of the answer proves that $4$ is the smallest: it is impossible to get the correct residue (mod 9) with 3 or less. Jan 12 awarded Nice Question Jan 7 awarded Nice Question Nov 24 awarded Guru May 29 awarded Yearling Apr 22 awarded Revival Mar 14 awarded Nice Answer Mar 7 comment Complex analysis textbook advise I think you will find that Needham really does concentrate on the most important stuff - for a serious understanding of what matters in complex analysis. Note sure that size is relevant. Mar 7 comment Definite Integral of $\sin^4(x)\cos(x).$ What exactly does "them" mean in that comment? Mar 7 answered Complex analysis textbook advise Feb 26 comment Sum and Divisibility Puzzle The title is very misleading - this has nothing to do with unique factorisation. Feb 26 revised Sum and Divisibility Puzzle Retagged Feb 24 answered Integration and measure theories, a reference list Feb 24 comment if $x^3-x\in\mathbb{Z}$ and $x^4-x\in\mathbb{Z}$ for some $x\in\mathbb{R}$, then $x\in\mathbb{Z}$. Hmm - you seem to have changed the roles of $a$ and $b$ ... and your statement (2) isn't actually a statement? Feb 24 comment if $x^3-x\in\mathbb{Z}$ and $x^4-x\in\mathbb{Z}$ for some $x\in\mathbb{R}$, then $x\in\mathbb{Z}$. Not sure, but I am a bit baffled by your first 2 lines. From your assumptions, it follows that $x+a = x^3$, but you seem to be claiming that $x+a = x.x^3$ - how did you get that? Feb 24 awarded Enlightened Feb 24 awarded Nice Answer Feb 20 reviewed Approve Curious representation of primes Feb 20 comment In the Collatz function, why does $2^k-1$ reach $3^k-1$ after $2k$ steps, and could it be used to find divergent trajectories? Assuming anyone still believes that he really did have such a proof!