Questions tagged [collatz-sequence]

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

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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 ...
2
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3answers
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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 ...
19
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1answer
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 ...
15
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2answers
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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 ...
6
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3answers
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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 ...
4
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3answers
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? ...
3
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1answer
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,...
6
votes
2answers
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: <...
6
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1answer
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 (...
3
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2answers
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 ...
0
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1answer
99 views

Automate the Boring Stuff - Collatz Exercise

I wrote the following code for the Collatz exercise: The Collatz Sequence Any feedback is appreciated. Write a function named collatz() that has one parameter ...
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3answers
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Finding the longest Collatz Sequence

Inspired by Project Euler 14: Longest Collatz Sequence "Which starting number, under one million, produces the longest Collatz Sequence chain?" I wrote the following Java code: ...