17 questions linked to/from Collatz Conjecture (OEIS A006577)
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### 1, 2, Fizz, 4, Buzz

Introduction In our recent effort to collect catalogues of shortest solutions for standard programming exercises, here is PPCG's first ever vanilla FizzBuzz challenge. If you wish to see other ...
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### Tips for golfing in PowerShell

What general tips do you have for golfing in Windows PowerShell? I'm looking for ideas that can be applied to code golf problems in general that are at least somewhat specific to PowerShell (e.g. "...
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### Does the code terminate?

This is a code golf challenge I thought of with a mathematical bent. The challenge is to write the shortest code possible such that it is an open question whether or not the code terminates. An ...
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### Return 1 - Popularity Contest [closed]

The Task Create a function/subroutine which returns 1. You can make it as elaborate as you like, as long as it returns 1. The Rules The entry with the most upvote wins - just like any popularity ...
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### Tips for golfing in Rust

While Rust is very, very rarely competitive in code golfing competitions (Java is often shorter), it can still be fun to golf in. What are some tricks for making Rust code shorter? Please post only ...
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### Tips for golfing in Julia

What general tips do you have for golfing in Julia? I'm looking for ideas that can be applied to code golf problems in general that are at least somewhat specific to Julia (e.g. "remove comments" is ...
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### Collatz's ice cream cone factory

The Collatz sequence Given a positive integer $a_1$, the Collatz sequence with starting value $a_1$ is defined as a_{n+1} = \begin{cases} a_n/2 & \mathrm{if}\ a_n\ \mathrm{is}\...
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### Recursive Collatz Conjecture

The Collatz conjecture postulates that if you take any positive integer, then repeat the following algorithm enough times: ...
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### Hitting 495 (Kaprekar) [duplicate]

Input: A three digit number from stdin or as an argument not all digits are the same may start with one or two zero's Process Order the input-digits ascending and descending to form two new ...
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### Tribute to John Conway: Collatz in FRACTRAN

John Horton Conway was a brilliant mathematician. Among his contributions were three Turing-complete esolangs: Game of Life (esolangs wiki), FRACTRAN (esolangs wiki), and Collatz function (esolangs ...
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### Extract and Divide

Challenge For a given positive integer $n$: Repeat the following until $n < 10$ (until $n$ contains one digit). Extract the last digit. If the extracted digit is even (including 0) multiply ...
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### Print the Super Collatz numbers

The Collatz Sequence (also called the 3x + 1 problem) is where you start with any positive integer, for this example we will use 10, and apply this set of steps to it: ...
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### Build a golfing language with me

A lot of PPCG users helped with the creation of this challenge, both in chat and the Sandbox, specifically Martin Ender, AdmBorkBork, Emigna and user202729 Our community has found it necessary to ...
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### Count the reviews!

Introduction and Credit Imagine you're Amazon. Imagine you have a large number of products for which a lot of people have written reviews scoring 1-5 stars. Now you need to give your customers a ...
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