Search Results
| Search type | Search syntax |
|---|---|
| Tags | [tag] |
| Exact | "words here" |
| Author |
user:1234 user:me (yours) |
| Score |
score:3 (3+) score:0 (none) |
| Answers |
answers:3 (3+) answers:0 (none) isaccepted:yes hasaccepted:no inquestion:1234 |
| Views | views:250 |
| Code | code:"if (foo != bar)" |
| Sections |
title:apples body:"apples oranges" |
| URL | url:"*.example.com" |
| Saves | in:saves |
| Status |
closed:yes duplicate:no migrated:no wiki:no |
| Types |
is:question is:answer |
| Exclude |
-[tag] -apples |
| For more details on advanced search visit our help page | |
Results tagged with co.combinatorics
Search options not deleted
user 99278
Enumerative combinatorics, graph theory, order theory, posets, matroids, designs and other discrete structures. It also includes algebraic, analytic and probabilistic combinatorics.
3
votes
Accepted
Covering sequences of words
Try $w_0 = b$, $w_1 = bab$, $w_2 = baba^2bab$, $w_3 = baba^2baba^3baba^2bab$, and recursively $w_{i+1} = w_ia^{i+1}w_i$.
Then $\displaystyle \limsup_{i \rightarrow \infty} Pr(w_i,a^n) = \lim_{i \rig …
- 399
3
votes
Sum of multinomial coefficients (even distribution)
If you take the averaged sum over all choices of signs $$\frac{1}{2^k}
\sum_{\varepsilon_i = \pm 1} (\varepsilon_1x_1 + \cdots +
\varepsilon_kx_k)^r$$ we see that only the terms with even exponents …
CommunityBot
- 1
1
vote
Bound of area of intersection
Since the geometry is irrelevant and you are just considering $n$ subsets of equal measure, $I(n,S,k)$ is also the maximum value such that, given any $n$ measure-$S$ subsets of the unit-circumference …
- 399
1
vote
Ratio between number of nodes and leaves in a rooted binary tree
We can prove a lower bound on the expression by considering only vertices immediately below a leaf:
$$\frac{[\sum_{v \in T \text{ not a leaf}}2^{h(v)}L(T(v))] + L(T)}{N(T)} \geq \frac{[\sum_{v \text{ …
- 399