All about flooble | fun stuff | Get a free chatterbox | Free JavaScript | Avatars    
perplexus dot info

Home > Numbers
1 to 9 concatenation (Posted on 2016-04-12) Difficulty: 3 of 5
What is the largest number n so that n, 2n, and 3n together contain every digit from 1-9 exactly once?

Analytical solution preferred.

No Solution Yet Submitted by Ady TZIDON    
No Rating

Comments: ( Back to comment list | You must be logged in to post comments.)
re: computer solution | Comment 7 of 8 |
(In reply to computer solution by Charlie)

But adding those zeros makes clear the reason for the pattern I spotted:

Each solution has a 1 digit part with no carry and a 2 digit part with no carry.

Consider 192 as two parts: 19 and 2
19->38->57
2->4->6
which together contain all the digits.  The parts can be permuted so we get two solutions 192 and 219.
(zeros can be inserted between or at the end)

273 works the same way, hence 327.

  Posted by Jer on 2016-04-13 07:21:29
Please log in:
Login:
Password:
Remember me:
Sign up! | Forgot password


Search:
Search body:
Forums (0)
Newest Problems
Random Problem
FAQ | About This Site
Site Statistics
New Comments (0)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Chatterbox:
Copyright © 2002 - 2024 by Animus Pactum Consulting. All rights reserved. Privacy Information