---
id: 5900f4551000cf542c50ff67
challengeType: 5
title: 'Problem 232: The Race'
---
## Description
Two players share an unbiased coin and take it in turns to play "The Race". On Player 1's turn, he tosses the coin once: if it comes up Heads, he scores one point; if it comes up Tails, he scores nothing. On Player 2's turn, she chooses a positive integer T and tosses the coin T times: if it comes up all Heads, she scores 2T-1 points; otherwise, she scores nothing. Player 1 goes first. The winner is the first to 100 or more points.
On each turn Player 2 selects the number, T, of coin tosses that maximises the probability of her winning.
What is the probability that Player 2 wins?
Give your answer rounded to eight decimal places in the form 0.abcdefgh .
## Instructions
## Tests
```yml
tests:
- text: euler232() should return 0.83648556.
testString: 'assert.strictEqual(euler232(), 0.83648556, "euler232() should return 0.83648556.");'
```
## Challenge Seed
```js
function euler232() {
// Good luck!
return true;
}
euler232();
```