Reputation
3,562
Top tag
Next privilege 5,000 Rep.
Approve tag wiki edits
Badges
1 17 48
Impact
~148k people reached

16h
comment Does the sum of the Zeta function taken on natural numbers converge?
You can just ask the machine before you ask here.
May
20
revised Solving $e^\frac1x = x$ non-graphically?
deleted 8 characters in body
May
20
revised Solving $e^\frac1x = x$ non-graphically?
added 109 characters in body
May
20
answered Solving $e^\frac1x = x$ non-graphically?
May
19
comment Approximating $e^{x}/(e^{x} - 1)$
:) Infamously known as $\sum_{n=0}^\infty n\,(1-x)^n=-\frac {1}{12}+\frac {1}{x} \left( \frac { e^x }{ e^x -1}- \frac {1}{2} \right)+\mathcal{O}(x^2)$.
May
19
comment Calculate $\lim_{n\to\infty}\frac{5n^n}{3n!+3^n}$
Consider $\frac{6\cdot 6\cdot 6\cdot 6\cdot 6\cdot 6}{1\cdot 2\cdot 3\cdot 4\cdot 5\cdot 6}$.
May
19
awarded  Popular Question
May
8
comment prove inequality $\sum_{i=0}^{\infty} \frac{1}{(i+n)^2} < \int_0^{\infty} \frac{1}{(x+n)^2}dx$
For the problem you want to get at, if you can use the result of the Basel problem, you can shift the sum and have it be $\pi^2/6$ minus a term where general Harminic numbers might put you on track.
May
7
awarded  Informed
May
7
comment What makes differential forms special
On the one hand, I really like this answer. On the other, it could be read as just emphasizing that the co-case is more well behaved, but not indicating why. I feel the question next question would naturally be "why do vector fields not behave well under pullbacks, what is the obstacle?"
Apr
30
awarded  Popular Question
Apr
26
comment Geometric Interpretation of Fractional Derivatives
In this thread I answer a very similar question, pointing out how they emerge in stochastic dynamics.
Apr
23
comment what is the definition of Mathematics ?
You say the term mathematics defined by usage - do you mean as opposed to the concept it denotes? This makes me wonder to what you refer to in the second sentence in "the definition" - the one of the concept or the term/name of it? I guess the thing which is defined by usage of the term which denotes it is defined by that property, and then this definition doesn't change over time. Sorry if I was unnecessarily trying to analyze the statement.
Apr
22
comment List all functions f: {a, b, c} → {0,1 }.
@Jared: I doubt people who have the answer here straight know it because they have a perfect function space cardinality intuition. I'd say it suggest that the function space being called $Y^X$ is a good mnemonic. You also imply that a question being harder makes it more interesting, I'm dubious about that also.
Apr
22
revised If $a_n = \frac{e^{n}}{e^{2n}-1}$ how do I show that $a_{n+1} \leq a_n$?
added 1 character in body
Apr
22
comment List all functions f: {a, b, c} → {0,1 }.
@Jared: Why is that more interesting?
Apr
22
answered If $a_n = \frac{e^{n}}{e^{2n}-1}$ how do I show that $a_{n+1} \leq a_n$?
Apr
21
comment Determine whether or not $\neg q \to \neg (q \land (p \to \neg q))$ is a tautology
I'd suggest you think about what $q\to (p\to q)$ means and then you think again about the claim in question.
Apr
16
comment Is the product of all objects of a finite category an initial object?
What are the left and right projections out of $x\times x$ here? Once they are fixed, I feel I can always find a diagram so that it doesn't work out.
Apr
15
comment Second order PDE
You have seen proper formula formatting alla $\frac{{\mathrm d}y}{{\mathrm d}x}$ in edits of your other questions - why don't you apply the knowledge?