4,540 reputation
1028
bio website
location
age
visits member for 3 years, 11 months
seen 4 hours ago

Aug
17
reviewed Leave Closed Probability of ace in each hand
Aug
6
comment Deformable circle from a cubic Bezier approximation
What do you mean by "smoothness"? Do you want C2 continuity? G2? Something else?
Jul
31
comment Lower bound for a relative of the central binomial coeff
@Raphael, can you explain why there's a singularity at $-2+\sqrt{5}$? I see singularities at $-2-\sqrt{5}$ and $\frac{1}{4}$.
Jul
30
comment Lower bound for a relative of the central binomial coeff
@GerryMyerson, the central binomial coefficient has a rather neat product representation which allows an easy ad hoc proof of the bound. The only way I can see to get a similar product representation is to factor out a central binomial coefficient from each of the binomial coefficients in the second sum. Then bounding with $\frac{1}{\sqrt{m-2j-1}}\ge\frac{1}{\sqrt{m}}$ I get a non-Gosper-summable hypergeometric, and crudely bounding the terms to get a summable geometric sequence gives a worse bound than simply taking the first term of the original sum.
Jul
30
comment Prove equivalence of Diffie-Hellman shared secret
@codeomnitrix, $a \equiv b\pmod c$ is a shorthand notation for $\exists k : a - b = ck$
Jul
30
asked Lower bound for a relative of the central binomial coeff
Jul
23
comment Transforming a latin square into a sudoku
@EwanDelanoy, that was my first thought for a counterexample, but just permuting the rows to give leading column $147258369$ suffices.
Jul
23
comment Transforming a latin square into a sudoku
And similarly for the 9x9 case it should suffice to fix the top-left 6x6 block.
Jul
19
answered Factorial Taxicab Number
Jul
18
comment What is the count of the strict partitions of n in k parts not exceeding m?
The answer to "How many different sets $X_1, \ldots, X_m$...?" would seem to be $m$...
Jul
16
comment “I have found a dead body on my car.”
This seems to be more a question about the English language than about mathematical logic.
Jul
15
awarded  Cleanup
Jul
15
revised Question regarding permutations and combinations?
rolled back to a previous revision
Jul
13
comment common multiple polynominal time
What is a common multiple of two real numbers? Or, as an alternative phrasing, why is $1$ not always a solution?
Jul
12
revised The number of partitions of $n$ and the $n$th Fibonacci number.
added 26 characters in body
Jul
12
comment The number of partitions of $n$ and the $n$th Fibonacci number.
The main difference would seem to be that the first is correct notation and the second is meaningless. When $\operatorname{mod}$ is used as an infix function from $\mathbb{Z}\times\mathbb{N}^+$ to $\mathbb{N}$ you shouldn't separate it from its first argument. $(P_n \operatorname{mod} F_n) = P_n$ looks like a bizarre way of writing $0 \le P_n < F_n$, but $P_n = P_n \pmod{F_n}$ just looks like a tautology with a typo of $=$ for $\equiv$.
Jul
12
comment Describing all points 4000 miles from the north pole
It's impossible to answer the underlying question without first determining the model of the globe and the metric. I think that you're modelling the globe as a sphere (as opposed to an ellipsoid such as the WGS84) and measuring the 4000 miles in Euclidean 3-space (as opposed to geodesics on the surface of the globe). Is this correct?
Jul
11
answered Graph Theory, with algorithms like kruskal and something more
Jul
10
reviewed Leave Open How can I find the square root using pen and paper?
Jul
10
reviewed Close Smallest multiple whose digits are only ones and zeros