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33384
bio website sites.google.com/site/rknmodn
location Halifax, Canada
age 32
visits member for 4 years, 5 months
seen Feb 26 at 5:52

This account is no longer in use.


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!
Oct
1
comment How can I print decimals in hexadecimal in Maxima?
I wouldn't worry too much about it; the about page is crystal clear: the question is on-topic here. As with questions about applied mathematics and statistics, questions about computational mathematics receive a fair amount of bullying on this site. (I must say, I love the irony in how the "on hold as off topic" message links to the help center, which asserts that the question is "welcome".)
Oct
1
comment How can I print decimals in hexadecimal in Maxima?
(a) I think it's worth pointing out that GEdgar's comment contradicts the help page for this site; (b) this question is about using the software to do maths: converting a number into hexadecimal (what's not mathsy about that?).
Oct
1
comment How can I print decimals in hexadecimal in Maxima?
We welcome questions about: Software that mathematicians use.
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
15
comment Show Continuity Using Epsilon Delta Definiton
What happens if you attempt to do what it asks?
Sep
9
comment Finding the last two digits of a number by binomial theorem
Does, "compute the number" count as any other way? The number is 108347059433883722041830251.
Sep
5
comment Solving a system of equations using modular arithmetic modulo 5
Print(Concatenation([":",")"]),"\n");
Sep
5
comment How to find perpendicular vector to another vector?
Also, can you state which language the code is in?
Sep
2
comment Find the sum of all 4-digit numbers formed by using digits 0, 2, 3, 5 and 8?
I know how you feel. But it is useful to know how to solve problems computationally too, even if it is just to check human-written solutions. (By the way, what language is this?)
Aug
31
comment In how many ways can three numbers be selected from the numbers $1,2,\dots,300$ such that their sum is divisible by $3$?
Aside from the above, I found yours the best answer. Right to the point!
Aug
31
comment In how many ways can three numbers be selected from the numbers $1,2,\dots,300$ such that their sum is divisible by $3$?
I'd say the answer to that question is yes (but I don't know what it is).
Aug
31
comment In how many ways can three numbers be selected from the numbers $1,2,\dots,300$ such that their sum is divisible by $3$?
In the $(0,1,2)$ case, we can choose $100^3$ triples.
Aug
30
comment For what $n$ can $\pm 1\pm 2\pm 3 … \pm (n-1) \pm n = n+1$?
That's an assertion. Could you add a proof of this assertion into this answer?
Aug
30
comment Find order of $xy$ provided $x^2=e, y^3=e$ and $yxy=xy^2x$
It's somewhat implicit that saying e.g. "$x^2=e$" implies $x$ has order $2$, otherwise we'd instead say "$x=e$" (or not even introduce $x$). Perhaps I'm a bit too pedantic (but this kind of detail matters e.g. for automated theorem proving). Anyway, the answer is fine so I better +1 it.
Aug
30
comment Find order of $xy$ provided $x^2=e, y^3=e$ and $yxy=xy^2x$
Hmm... it could be that $x=e=y$ too (in which case $xy=e$ has order $1$). The question doesn't say e.g. "the order of $x$ is $2$". [It must be a divisor of 3, though. So it's either $3$ or $1$.]
Aug
29
comment Problem on directed graph involving $\gcd$
The question for strongly connected digraphs is now here.
Aug
29
comment Problem on directed graph involving $\gcd$
It looks like a counterexample to me. I wonder if this is a homework question; the lecturer might have a surprise when the assignments are returned. (I suppose the theorem would be true if there were no "incoherent" cycles.)
Aug
29
comment Problem on directed graph involving $\gcd$
What is the value of $p$ if $G$ has no cycles?