Brian M. Scott's user avatar
Brian M. Scott's user avatar
Brian M. Scott's user avatar
Brian M. Scott
  • Member for 12 years, 9 months
  • Last seen this week
  • Cleveland Heights, OH
2 votes
Accepted

Prove that if G is a digraph who underlying graph is regular, then then following formula holds.

2 votes
Accepted

Graph theory and Combinatorics - how many walks?

2 votes

Inverse image of every compact set is compact under a function

2 votes
Accepted

Prove that in the union of two trees there exist a vertex with degree of at most $3$

2 votes

When does the cardinality disappear?

2 votes
Accepted

How many strings of $3$ decimal digits have exactly two digits as $4$?

2 votes
Accepted

Question about Chapman's *An involution on derangements*

2 votes

Simple example of a regular topological space that is not first countable or not metrisable?

2 votes

Proving the number of leaves is larger by at least two than the number of vertices with a degree of at least 3

2 votes

Finite fields properties

2 votes
Accepted

Is $\mathbb{R}^{2}$ separable for the railmetric( or SNCF -metric or post-office metric)?

2 votes
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Intersection of two filters on a poset

2 votes

(Combinatorics) number of compositions of $n$ into $k$ parts so that $i$-th part is not larger than $a_i$

2 votes
Accepted

If $U \subset S \subset X$, $U$ is open in $S$, and $S$ is open in $X$, then $U$ is open in $X$.

2 votes
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Two combinatorial identities: $\sum\limits_{k=0}^{n} \binom{n}{k}k2^{n-k}$ and $\sum\limits_{k=1}^{n-2} \binom{n}{k}\frac{k}{n-k}$

2 votes
Accepted

Cardinality argument in proving that not every Lebesgue measurable set is a Borel set

2 votes
Accepted

$S(\Omega \sqcap A)=S(\Omega)\sqcap A$ Halmos Measure Theory

2 votes

Prove that language is non-context free $L=\{a^{n^2}b^n|n\ge 0\}$

2 votes
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Proving that $\Delta x^{(n)} = n x^{(n-1)}$

2 votes
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A uniform space must be a symmetric space.

2 votes
Accepted

A (possibly T1) topological space has a dense subset which is homeomorphic to the whole space. What can be said about the space?

2 votes

Sets,transversals,PT property,cardinals

2 votes
Accepted

Number of groups of five balls such that the sum of all the balls is even

2 votes
Accepted

If $X$ admits a nearest point to each point in every metric super space of $X$: every point like function on $X$ attains it's minimum value on $X$.

2 votes
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ODE, a first order none-linear equation with ratios and exponents

2 votes
Accepted

$32$ Goldbach Variations - Papers presenting a single gem in number theory or combinatorics from different point of view

2 votes

$B$ is a subset of some $s(n)$

2 votes
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If a mapping $g: \mathbb{R} \to \mathbb{R}$ is strictly increasing, is it an open map?

2 votes
Accepted

Topological properties that the real line does not have

2 votes
Accepted

A mathematics competition had 9 easy and 6 difficult problems

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