# omnimath / omnimath_3383

- taskset: [omnimath](https://harnessreport.com/tasks/omnimath.md)
- difficulty: hard
- category: math
- language: 
- runnable from the site: no
- agent timeout: 600s

## Results by harness

_none yet_

## Instruction

```
# Mathematical Problem

One day, there is a Street Art Show at somewhere, and there are some spectators around. We consider this place as an Euclidean plane. Let $K$ be the center of the show. And name the spectators by $A_{1}, A_{2}, \ldots, A_{n}, \ldots$ They pick their positions $P_{1}, P_{2}, \ldots, P_{n}, \ldots$ one by one. The positions need to satisfy the following three conditions simultaneously. (i) The distance between $K$ and $A_{n}$ is no less than 10 meters, that is, $K P_{n} \geq 10 \mathrm{~m}$ holds for any positive integer $n$. (ii) The distance between $A_{n}$ and any previous spectator is no less than 1 meter, that is, $P_{m} P_{n} \geq 1 \mathrm{~m}$ holds for any $n \geq 2$ and any $1 \leq m \leq n-1$. (iii) $A_{n}$ always choose the position closest to $K$ that satisfies (i) and (ii), that is, $K P_{n}$ reaches its minimum possible value. If there are more than one point that satisfy (i) and (ii) and have the minimum distance to $K, A_{n}$ may choose any one of them. For example, $A_{1}$ is not restricted by (ii), so he may choose any point on the circle $C$ which is centered at $K$ with radius 10 meters. For $A_{2}$, since there are lots of points on $C$ which are at least 1 meter apart from $P_{1}$, he may choose anyone of them. (1) Which of the following statement is true? (A) There exist positive real numbers $c_{1}, c_{2}$ such that for any positive integer $n$, no matter how $A_{1}, A_{2}, \ldots, A_{n}$ choose their positions, $c_{1} \leq K P_{n} \leq c_{2}$ always hold (unit: meter); (B) There exist positive real numbers $c_{1}, c_{2}$ such that for any positive integer $n$, no matter how $A_{1}, A_{2}, \ldots, A_{n}$ choose their positions, $c_{1} \sqrt{n} \leq K P_{n} \leq c_{2} \sqrt{n}$ always hold (unit: meter); (C) There exist positive real numbers $c_{1}, c_{2}$ such that for any positive integer $n$, no matter how $A_{1}, A_{2}, \ldots, A_{n}$ choose their positions, $c_{1} n \leq K P_{n} \leq c_{2} n$ always hold (unit: meter); (D) There exist positive real numbers $c_{1}, c_{2}$ such that for any positive integer $n$, no matter how $A_{1}, A_{2}, \ldots, A_{n}$ choose their positions, $c_{1} n^{2} \leq K P_{n} \leq c_{2} n^{2}$ always hold (unit: meter).

## Instructions

Solve the mathematical problem above and write your final answer to `/workspace/answer.txt`.

**Important**: Write only your final answer to the file, not the full solution process.

### Guidelines

- Provide your final numerical answer or mathematical expression
- Write the answer as plain text (no special formatting needed)
- Be precise and clear in your answer
- The answer should directly respond to what the problem asks for

### Example

If the problem asks "What is 2 + 2?", your answer file should contain:

```
4
```

Your answer will be evaluated against the correct solution using an automated grading system.
```
---
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