# Questions tagged [pattern-matching]

The pattern-matching tag has no usage guidance.

12
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4
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2
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### Number of Salem–Spencer subsets of $\{1,2,3,\dots ,n\}$

I was wondering about sets that do not contain any $3$-term AP, and came to know that the official name of such a set is Salem–Spencer set. I was considering the question of counting the number of ...

3
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0
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239
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### On thickness of binary polynomials

OEIS A169945 introduces the concept of thickness of a polynomial as the magnitude of the largest coefficient in the expansion of the square of the polynomial. Considering the $2^{n+1}$ polynomials $p(...

-2
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1
answer

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### Can the same dataset be described as Chaotic & Pareto/ Power law distribution?

I'm trying to abstract the mathematical part of the problem as much as possible before the details follow,
There's this dynamic data set that's $O(2^{32})$, a recent result described it as a power-law ...

0
votes

1
answer

152
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### Find cycles with specific weights in complete graph

Assume I have an undirected edge-weighted complete graph $G$ of $N$ nodes (every node is connected to every other node, and each edge has an associated weight). Assume that each node has a unique ...

2
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0
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151
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### Graph pattern matching

Given a weighted, oriented, connected graph with $10^7$ vertices and $10^{10}$ edges I need to implement the algorithm for searching various patterns on this graph for less than polynomial time.
...

2
votes

1
answer

119
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### What is the most appropriate ML technology or math tool for classifying/recognizing 2D scatter plot shapes? [closed]

I would like to be able to automatically classify an input scatter plot into a limited, predefined set of 2-D scatter plots (see attached image), such as a Circle, a Cross, a Straight Line and a Curvy ...

12
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2
answers

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### Why does this Moiré pattern look this way?

I was making some gifs of Mobius transformations in Matlab, and some strange patterns began to appear. I'm not sure if a deeper knowledge of the filetype/algorithm is needed to understand this ...

2
votes

0
answers

231
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### On the cardinality of the set of right-truncatable primes

We say that the (base ten) prime number $p=a_{n}a_{n-1}a_{n-2}\cdots a_{1}a_{0}$ is right-truncatable if all of the following numbers are prime:
\begin{eqnarray*}a_{n},\\a_{n}a_{n-1},\\ a_{n}a_{n-1}...

1
vote

0
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123
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### Expressing Numbers with a Minimal Sum in Powers of 2 [closed]

The first 64 bits of pi are:
11.00100100001111110110101010001000100001011010001100001000110100
Computer multiplication can be sped up by looking for patterns and ...

1
vote

1
answer

481
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### Shortest absolute value of path in graph

Suppose we have a weighted, acyclic digraph, with positive and negative edge weights.
Is there an algorithm that determines whether there is a path of weight zero between vertices A and B? The ...

9
votes

2
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352
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### Finding local patterns in a circular list

Consider a list $\boldsymbol{x}=x_0,x_1,\ldots,x_{n-1}$, which we consider to be circular by taking the subscripts modulo $n$. The entries in the list are distinct integers.
A local pattern is a ...

3
votes

1
answer

311
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### Stricter permutation patterns

(I asked this ten days ago on math.SE, but I received no reply, so I'm trying again here.)
A lot of work has been done on patterns in permutations, where a permutation is said to match a given ...