143 reputation
9
bio website nayuki.io
location Toronto, Canada
age 26
visits member for 3 years, 3 months
seen Jul 29 at 21:42

Software development and computer science for the win!

See my web site for the kinds of stuff I play with: http://www.nayuki.io/

Career profile: http://careers.stackoverflow.com/nayuki


Nov
7
awarded  Popular Question
Sep
28
awarded  Critic
Sep
28
comment How to write this in mathematical notation?
In your question, "either x or y" is misleading because it is possible for both x and y to be irrational and have their product be irrational too.
Sep
24
awarded  Popular Question
Apr
16
comment Prove that $\lfloor \lfloor x / a\rfloor / b \rfloor = \lfloor x / (ab) \rfloor$
(a) Is $k$ constrained to be an integer? (b) How does your proof address the fact that $m$ and $n$ must be positive integers (not arbitrary real numbers)?
Apr
16
comment Prove that $\lfloor \lfloor x / a\rfloor / b \rfloor = \lfloor x / (ab) \rfloor$
@MathGems: I looked at your proof, but I'm not convinced about why those bi-implications are true. I found the proof by Brian M. Scott to be better explained and easier for me to understand.
Apr
13
comment Prove that $\lfloor \lfloor x / a\rfloor / b \rfloor = \lfloor x / (ab) \rfloor$
Wow André, that was a pretty terse hint. But with some work, I was able to expand it into a full solution. Thanks!
Apr
13
comment Prove that $\lfloor \lfloor x / a\rfloor / b \rfloor = \lfloor x / (ab) \rfloor$
You're right. Though I feel embarrassed about asking a duplicate question, I'd like thank you very much!
Apr
13
asked Prove that $\lfloor \lfloor x / a\rfloor / b \rfloor = \lfloor x / (ab) \rfloor$
Mar
3
awarded  Commentator
Mar
3
comment Prove that if $2^n-1$ is prime, then $n$ divides $2^n-2$
I mean introduction of a new variable, whose role and meaning is unexplained.
Mar
3
comment Prove that if $2^n-1$ is prime, then $n$ divides $2^n-2$
I am extremely uncomfortable with how much you left implied, such as the instantiation of $K$, the references to GCD, and the very non-obvious invocation of Fermat's little theorem for $K$. Only after rereading your proof a few times on separate days did I start to believe that it plausibly leads to an answer at all. -1.
Mar
3
comment Prove that if $2^n-1$ is prime, then $n$ divides $2^n-2$
I didn't understand how your answer fits with my question. Please see the other answers as examples of proofs that I did understand.
Mar
2
comment Prove that if $2^n-1$ is prime, then $n$ divides $2^n-2$
Other than that, I'm sorry but I don't understand your argument at all.
Mar
2
comment Prove that if $2^n-1$ is prime, then $n$ divides $2^n-2$
Why are all your variables in uppercase?
Feb
29
accepted Prove that if $2^n-1$ is prime, then $n$ divides $2^n-2$
Feb
28
awarded  Editor
Feb
28
revised Prove that if $2^n-1$ is prime, then $n$ divides $2^n-2$
Added better answer
Feb
27
comment Prove that if $2^n-1$ is prime, then $n$ divides $2^n-2$
Alternate explanation: $p$ divides $2^n-1$, so $2^n-1$ divided by $p$ leaves no remainder, thus $2^n-1 \equiv 0 \mod p$.
Feb
27
comment Prove that if $2^n-1$ is prime, then $n$ divides $2^n-2$
Ohh right, I understand now. I guess I'm not comfortable enough with modular arithmetic that such an elementary fact slipped past me, heh.