9,909 reputation
2933
bio website
location
age 38
visits member for 2 years, 9 months
seen 5 mins ago

23h
answered What is the inverse of the divisor sum function $\sigma $?
1d
comment How to efficiently find the largest perfect square dividing a given large integer?
@user157920 It is possible to factor $n$ in much faster time than $O(\sqrt{n})$. Don't assume other people didn't factor $n$.
2d
comment Solving the Diophantine equation $ax + by = c$ using Maple
For code, just enclose the whole thing in backticks `` instead of $$ on each line. I edited it for you.
2d
revised Solving the Diophantine equation $ax + by = c$ using Maple
reformatted code
2d
comment Solving the Diophantine equation $ax + by = c$ using Maple
How do you expect someone to answer this with no implementation details? Debugging invisible code is definitely off-topic :).
2d
comment Is recursion a type of iteration?
You might be interested in reading en.wikipedia.org/wiki/…, which might be a reasonable representative of "iteration". Then compare it to en.wikipedia.org/wiki/Ackermann_function, which has a simple recursive definition. In some sense recursion is more powerful than iteration, but as Thomas Andrews points out, it really depends on how you define each term.
2d
answered Proof of non divisibililty of $\binom{n}{r}$ with a prime $p$
Jan
23
comment What is the inverse of the divisor sum function $\sigma $?
@ndroock1 I'm unclear on what you mean by computable. What is non-computable about any of these formulas?
Jan
23
comment What is the inverse of the divisor sum function $\sigma $?
Would you prefer $\mu(n) *n\mu(n)$? It isn't any more computable, but it is shorter.
Jan
23
comment $x=yx$. If I assume, $x\neq{0}$ then how to find for $x$ in terms of $y$?
@SufyanSheikh You can't divide by $0$. Therefore you can't divide by $x$ without first assuming $x \ne 0$.
Jan
21
comment Can someone give me an example of an M-Sequence please?
Why not give yourself an example? Pick any $k \ge 1$ and choose any values for $f_0,\ldots,f_k$ (it would be good to start with non-zero values). Then write down what the definition means in this particular case.
Jan
21
comment Is zero an even number?
@AlanSutherland The parity of zero is only unusual in that many people are miseducated about it from childhood and seem to retain a sense of confusion and wonder even though the objective evidence is clear and straightforward :).
Jan
21
comment Subfield generated by a multiplicative subgroup of the field
What if $F$ is the field of rational functions $\mathbb F_p(x)$ and $X = \langle x \rangle$? Is it possible to express $1/(x+1) \in K$ as a linear combination of $\{x^{r} : r \in \mathbb Z\}$?
Jan
21
comment Is there an efficient method to search prime factors near $9^{9^9}$?
@Henrik Presumably, "special" in the sense that it has the compact representation $9^{9^9}$ rather than being a random number with hundreds of millions of digits. (Akin to the sense of en.wikipedia.org/wiki/Special_number_field_sieve)
Jan
20
comment proving that $ab$ is a perfect square.
@SandeepSilwal I never claimed $ab \equiv 3 \pmod p$, nor is it expected by the problem. It appears you are confused about the meaning of the Legendre symbol: en.wikipedia.org/wiki/Legendre_symbol
Jan
19
comment Is $\sum_{n=1}^\infty \frac{1}{2^{n^2}}$ is rational number?
I'm curious what theorem proves it to be transcendental?
Jan
19
comment Find all the positive integers $m$ such that $p_{m}≥2m$
Sorry, you're right, I didn't notice the reference to Rosser 1938.
Jan
19
comment Find all the positive integers $m$ such that $p_{m}≥2m$
Isn't this the complement of the desired set?
Jan
19
comment Find all the positive integers $m$ such that $p_{m}≥2m$
Isn't the $\log \log n - c$ term important here?
Jan
19
answered Find all the positive integers $m$ such that $p_{m}≥2m$