Questions tagged [collatz-sequence]

This tag should be used for code related to the sequences described in the Collatz conjecture.

12 questions
1k views

Project Euler problem 14 (longest Collatz sequence) in Swift 3

I was trying to solve Project Euler:Problem 14 using Swift 3, but it takes ages to give me an answer, which is a sign that my code is absolute garbage performance-wise. What could I do to increase the ...
2k views

Determine Collatz sequence length for given starting values

I am trying to get into the habit of solving programming puzzles in my spare time but am stuck on the first one (which I know can be for a large number of reasons, hence my posting for help). Shown ...
263 views

Streaming Collatz

Challenge The recent question The 3n + 1 algorithm for a range inspired me to investigate a Java-8 dependent streaming mechanism for solving the programming challenge: For any two numbers ...
2k views

Automate the Boring Stuff with Python - The Collatz sequence project

I am new to programming and started learning with Automate the Boring Stuff with Python. I just completed chapter 3's "Collatz sequence" project. I was wondering what would you do differently and ...
12k views

Hailstone Sequences in Python

For the problem given: Douglas Hofstadter’s Pulitzer-prize-winning book, Gödel, Escher, Bach, poses the following mathematical puzzle. Pick a positive integer $n$ as the start. If $n$ is ...
978 views

Generator for the collatz conjecture sequence

I tried to write this code as concisely as possible. Is this the best way to do it? ...
574 views

Project Euler #14 (Longest Collatz sequence)

A Collatz sequence for a given positive integer $n$ is to take half of $n$ if even and $3n+1$ if $n$ is odd; repeat until the value goes to $1$. The question is which number from 1 to 1,000,...
485 views

UVA 100: “The 3n + 1 problem”

I’ve solved UVA Problem 100: The 3n + 1 problem . In short, the task was to write a program that calculates a maximum of Collatz sequence lengths for any given range of starting values. My program: <...
315 views

Locating the largest Collatz Sequence with memoization

Inspired by this question I wrote a memoized form of the collatz sequence calculator. The idea was to cache the sequence lengths for as many sequences as possible, from 0 to some value. I managed to (...
140 views

Contest Solution: Hailstones

The Problem In the January 1984 issue of Scientific American, an interesting sequence of numbers known as a hailstone series was described. The series is formed by generating the next number ...