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Zyx
  • Member for 7 years, 9 months
  • Last seen more than a month ago
13 votes
1 answer
332 views

What is the name of this class of (combinatorial?) problems?

6 votes
4 answers
199 views

Common proof for $(1+x)(1+x^2)(1+x^4)...(1+x^{2^n})=\dfrac{1-x^{2^{n+1}}}{1-x} $

4 votes
0 answers
53 views

Is there a deep connection between the urn problem and the sum of powers?

4 votes
2 answers
182 views

Prove that $\sum^m_{k=0}\binom{m}{k}(-1)^k(\frac{1}{n+k+1}) = \frac{m!n!}{(m+n+1)!}$

3 votes
0 answers
48 views

How to decide whether a sequence, defined with a quadratic map converges or not?

3 votes
3 answers
58 views

What are the necessary conditions for $\delta =\min \left\{ f^{-1}\left( x_{0}-\varepsilon \right) ,f^{-1}\left( x_{0}+\varepsilon \right) \right\}$?

3 votes
5 answers
2k views

A simpler proof of $(1-x)^n<\frac{1}{1+nx}$

3 votes
1 answer
229 views

Extending compass and straightedge construction with pins and strings.

2 votes
1 answer
666 views

Sequence of integers that contains all combinations of digits with no repeating digits

2 votes
2 answers
183 views

What can we say about the prime factors of $‚Äč^{10}10+23$?

2 votes
2 answers
808 views

What does $[ \forall x\left( P\left( x\right) \Rightarrow q\right) ] \Leftrightarrow [ \left( \exists x:P\left( x\right) \right) \Rightarrow q]$ mean?

2 votes
2 answers
94 views

How to interpret big $\bigcup_{i\in I}\bigcap_{j\in J}M_{i,j}$ and $\bigcap_{j\in J}\bigcup_{i\in I}M_{i,j}$

1 vote
3 answers
748 views

Find the closed formula for $\sum_{i=0}^n a^{n-i} \cdot b^i$

1 vote
2 answers
193 views

Use of zero to the power of zero

1 vote
0 answers
74 views

What is the official name for this concept?

1 vote
1 answer
421 views

Avoiding getting lost in the calculations

1 vote
1 answer
142 views

Is the following proof of convergence valid?

1 vote
0 answers
74 views

Relationship between prime factorization of $n+1$ and $nm+1$

1 vote
1 answer
67 views

Defining a sequence by recursively excluding elements.

1 vote
1 answer
92 views

Prove that $\sum _{i=0}^{p} \left( \binom {p+1}{i+1} \times \sum _{j=1}^{n} j^{p-i} \right)=(n+1)^{p+1}-1$

1 vote
2 answers
187 views

Prove that $\int{\frac{x^2}{(x^2 + a^2)^n}}dx = \int{\frac{1}{(x^2 + a^2)^n}}dx - a^2\int{\frac{1}{(x^2 + a^2)^{n+1}}}dx$

1 vote
2 answers
60 views

Question about $\lim_{n\rightarrow\infty} (\sqrt{n} - \sqrt{n - n^c})$ and $\lim_{n\rightarrow\infty} (\sqrt[3]{n + n^c} - \sqrt[3]{n})$

1 vote
1 answer
297 views

Determine whether a triangle with given side lengths is a right triangle, with special constraints on the calculation.

1 vote
3 answers
75 views

Error while integrating reciprocal of irreducible quadratic $\int{\frac{1}{ax^2 + bx + c}}{dx} = ?$

1 vote
2 answers
209 views

Proper way to calculate vector derivatives of $\|Ax - b\|^2$?

1 vote
0 answers
65 views

Difficulty understanding Armijo rule in the context of backpropagation

1 vote
0 answers
179 views

Calculate all possible combinations of symmetries on a 10x10 square grid

1 vote
0 answers
123 views

Find upright bounding rectangle of the intersection of two circles

1 vote
2 answers
81 views

Measures for homogeneity of a finite sequence - approximating an image with lines.

0 votes
0 answers
45 views

Determine whether an integer can be constructed from other integers by applying bitwise AND and OR operations