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13h
comment Unusual 3D Packing Problem
"You can see all $6$ edges." Doesn't a cube have $12$ edges?
20h
answered How to get a number that is divisible by $n$ - without obviously seeing it?
1d
revised count of Ordered Pairs such that their product is less than a number
deleted 75 characters in body
1d
comment count of Ordered Pairs such that their product is less than a number
@AlexJBest: Thanks, you're right.
1d
answered count of Ordered Pairs such that their product is less than a number
1d
comment Why all games are not Potential?
The potential $\Phi$ must have the defining property for all players simultaneously. This puts conditions on how the players' utilities must relate to one another.
2d
comment Poisson process: Has my book used a necessary condition, when it should have used a sufficient condition?
No, because in general knowing the distribution of the order statistics doesn't tell you anything about the distribution of the ranks of the random variables.
2d
comment integral $I=\int_{-\infty}^\infty e^{-\alpha x^{2k}}dx$
I know; but the power series can only converge if the function is analytic in some neighborhood of $\beta=0$ in the complex plane. It clearly isn't… presumably it has a branch cut at the origin.
2d
comment integral $I=\int_{-\infty}^\infty e^{-\alpha x^{2k}}dx$
Look at the original integral, and consider what would happen if $\beta$ were negative. You should be able to see why the power series in $\beta$ must have zero radius of convergence around $\beta=0$.
2d
comment Poisson process: Has my book used a necessary condition, when it should have used a sufficient condition?
If you know the joint distribution of $n$ continuous random variables, then you know everything there is to know about them. What else do you mean by "what kind of random variables [are we] dealing with"?
Apr
14
comment Find a value of $n$ that has exactly 32 divisors
Whether it's the easiest solution or not, $2310$ isn't the smallest solution.
Apr
14
answered Find a value of $n$ that has exactly 32 divisors
Apr
14
comment Find a value of $n$ that has exactly 32 divisors
How about $2^{31}$? Its $32$ divisors are $2^0=1$, $2^1=2$, …, $2^{30}$, and $2^{31}$.
Apr
11
comment Error in thinking: Poisson Process is a Markov Process
Do you mean to say $N_{n-1}=X_{t_{n-1}}-X_{t_{n-2}}$, etc.? The way you have it written, the various $N_i$ are certainly not independent, because they involve overlapping intervals of time.
Apr
11
comment Probability Distribution of Runs in Coin Flips
Basically the same as this question: math.stackexchange.com/questions/59738/…
Apr
6
comment Simple Grammar Question
In Dr. Seuss, you've got Thing One and Thing Two. I think you'd say, "Call in Things One and Two," wouldn't you? It's not true that all uses of the words "theorem" and "lemma" should be capitalized; just those cases where they refer to a particular named theorem or lemma.
Apr
5
comment Heptagonal tesselations
No, a regular heptagon can't tesselate with any other set of regular polygons. The reason is that its interior angle ($5\pi /7$) can't be combined with the interior angles of other regular polygons to form $2\pi$.
Apr
3
answered Probability of objects being grouped together in a set of sets
Mar
28
comment Are there integers $a, b$ s.th. $\pi^a = e^b$?
Even if we knew that $\log \pi$ were irrational, it wouldn't prove that $\pi$ and $e$ were algebraically independent (though the converse does hold). This isn't a strict duplicate. That said, I doubt that $\log\pi$ has been proven to be irrational.
Mar
28
comment About the definition of fixed-point combinators
The parentheses are for grouping (assumed to be left-associative in the absence of parentheses), not function application. $y(f)$ and $y f$ mean the same thing. $f (y f)$ and $f y f$ do not; the latter is equivalent to $(f y) f$.