Problem 49572. Compute the largest number possible with the Brussels choice

Created by ChrisR
Appears in Combinatorics I

Difficulty:Rate

Solve Later
Add To GroupÃ‚

The Brussels choice (or Choix de Bruxelles) operation changes one number to another by taking a substring of the digits and either doubling it or (if the number is even) halving it. For example, starting with 9 and highlighting substrings, one can generate this sequence:
9, 18, 36, 312, 622, 644, 1288, 1488,...
Another possibility is 
9, 18, 116, 232, 464, 924, 1844, 1888,...
Both of these excerpts have eight entries, but the second ends in a larger number than the first. 
Write a function that takes an initial value  and determines the largest number  resulting after n steps. In the above examples,  = 9 and . Return the number as a character string.

Solve

Solution Stats

69 Solutions
12 Solvers

Last Solution submitted on Apr 15, 2024

Last 200 Solutions

Problem Comments

2 Comments

2 Comments

William on 24 Dec 2020

Chris, -- In the first example, is the fourth number supposed to be 312 rather than 112, or am I misunderstanding the description?

ChrisR on 24 Dec 2020

Yes, you're right. Thanks. If you start with 1, you will see why I made that mistake.

Solution Comments

Show comments

Problem Recent Solvers12

Problem Tags

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Problem 49572. Compute the largest number possible with the Brussels choice

Solution Stats

Last 200 Solutions

Problem Comments

Solution Comments

Problem Recent Solvers12

Suggested Problems

More from this Author291

Problem Tags

Community Treasure Hunt

Problem 49572. Compute the largest number possible with the Brussels choice

Solution Stats

Last 200 Solutions

Problem Comments

Solution Comments

Problem Recent Solvers12

Suggested Problems

More from this Author291

Problem Tags

Community Treasure Hunt

Players