Benjamin Dickman
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 Apr 17 awarded Yearling Mar 7 awarded Good Answer Mar 5 awarded Mortarboard Mar 5 awarded Enlightened Mar 5 awarded Nice Answer Mar 5 answered Why is the Frankl conjecture hard? Mar 1 comment Does there exist a sum of two squares which is written in MORE than 4 distinct way? Ah, I was talking about $325^2$, rather than $325$, which you can see described in OEIS A097101. The seven pairs $(x, y)$ for which $x^2 + y^2 = 325^2$ are: $(36, 323), (80, 315), (91, 312), (125, 300), (165, 280), (195, 260), (204, 254)$. (In any event: I've voted to close the question since it is certainly not research level...) Feb 2 awarded Nice Answer Jan 14 comment Improvement of a bound on divisor distributions from “Divisors” (Hall and Tenenbaum)? Although the accepted response already leads to Ford's paper, you might also consult the answer to this earlier question: MO 108912 Dec 17 awarded Necromancer Dec 12 awarded Necromancer Dec 9 comment Sophisticated treatments of topics in school mathematics Maybe an example is captured by the notion of "simplifying" as discussed in MO 126519? Dec 1 comment Exact formula for $\sum_{n=0}^{+\infty}\frac1{n^2+1}$ WolframAlpha does accurately evaluate this series; however, the value was initially mis-recorded here. (Hence the edit.) Dec 1 revised Exact formula for $\sum_{n=0}^{+\infty}\frac1{n^2+1}$ WolframAlpha correctly evaluates the series; I have fixed its mistranscription. Nov 29 comment How has “what every mathematician should know” changed? Related to $\pi$ and its being irrational (as well as the infinitude of the primes): See MO 21367 and the fascinating answer of François G. Dorais. Nov 18 revised Has the Fundamental Theorem of Algebra been proved using just fixed point theory? Finally found that Kulpa paper! Many thanks to K. Szumiło. Nov 12 comment Proofs without words See also: MESE 220. Nov 9 comment A different kind of divisor sums I think your initial recording of the sequence got cut off, since it ends with a $1$ (which won't be the case for any $n > 1$). Also, any prime $p$ will have only divisors $1$ and $p$ hence only sums $2$, $1+p$, and $2p$; in particular, the sequence will record a $3$ at the primes. To this end, I wonder whether considering the sequence for $n$ composite could be helpful? (Though one could similarly argue that $p^2$ a squared prime will only have sums $2$, $1+p$, $1+p^2$, $2p$, $p+p^2$, and $2p^2$, which are distinct, and thus explain the $6$ that arises for your fourth and ninth entries...) Nov 2 comment Forcing is intuitionistic Have you checked Kreisel (1961) "Set-theoretic problems suggested by the notion of potential infinity"? As mentioned in MO 124011, Kreisel claimed he had a form of forcing in his interpretation of intuitionism in that paper. (Cf. the historical treatment of forcing by G.H. Moore.) Oct 13 comment Simple bijection between reals and sets of natural numbers Do the interleaved blocks really go back to Dedekind? (I first saw this construction in the "Foundations" text by RL Wilder...)