Douglas S. Stones
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 Nov 11 awarded Nice Answer Nov 5 awarded Revival Oct 11 comment Perfect numbers less than 10 000 I'm not sure in Maple, but in GAP they can be found using Filtered([1..9999],i->Sum(DivisorsInt(i))=2*i); which returns [ 6, 28, 496, 8128 ]. It's just brute force computation; nothing intelligent. Oct 10 comment New hourly rate after a pay raise Does one really get 3 dollars for answering this question? I find that hard to believe. But, if it were true, by crowdsourcing, we don't even need to know any maths to make money. We can just copy/paste the questions here, and copy/paste the answers back for profit. Nice! Sep 24 comment Re-write $1 \cdot x$ to $x$. A large chunk of Adriano's proof (and the Prover9 proof) amounts to showing that $(x^{-1})^{-1}=x$. If we can assume this: $$1x=(xx^{-1})x=x(x^{-1}x)=x(x^{-1}(x^{-1})^{-1})=x1=x.$$ Sep 23 revised Prove that $\sum_{k=0}^r {m \choose k} {n \choose r-k} = {m+n \choose r}$ edited tags Sep 23 revised How to calculate no. of binary strings containg substring “00”? edited tags Sep 23 revised How to solve this using using stirling approx? edited tags Sep 21 answered Re-write $1 \cdot x$ to $x$. Sep 15 comment Show Continuity Using Epsilon Delta Definiton What happens if you attempt to do what it asks? Sep 12 answered Is the any application of vector that is only specific to biology or chemistry? Sep 12 revised “Monotone Convergence Theorem” $\implies$ “least upper bound property” edited tags Sep 12 revised Binomial and series with 2 coefficients Fixed error Sep 12 reviewed Leave Open A bijection of Cartesian products Sep 11 answered Solving 50! mod 103 Sep 10 reviewed Leave Open how do you call a function that breaks down on y? Sep 10 reviewed Leave Closed Is the $\sum\sin(n)/n$ convergent or divergent? Sep 10 reviewed Leave Closed Limit of the nested radical $\sqrt{7+\sqrt{7+\sqrt{7+\cdots}}}$ Sep 10 reviewed Leave Closed Why is $dy dx = r dr d \theta$ Sep 10 reviewed Leave Closed How to find the equation of a graph with given coordinates?