Baltic Way 2022 · Problem 10
Combinatorics
A natural number is said to be contained in the natural number if it is possible to obtain by erasing some digits from (in their decimal representations). For example, 123 is contained in 901523, but not contained in 3412.
Does there exist an infinite set of natural numbers such that no number in the set is contained in any other number from the set?
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Review
Topics
Pigeonhole and extremal arguments
Solutions
No verified local solution is currently available.
Contest context
Results from Baltic Way 2022
10 teams
- Mean score
- 0.5 / 5
- Scores of 4 or 5
- 1 / 10
- Estonia
- 0 / 5
Score distribution
09
10
20
30
40
51
All team scores
| Team | Score |
|---|---|
| Poland | 0 / 5 |
| Germany | 5 / 5 |
| Lithuania | 0 / 5 |
| Estonia | 0 / 5 |
| Denmark | 0 / 5 |
| Latvia | 0 / 5 |
| Sweden | 0 / 5 |
| Norway | 0 / 5 |
| Finland | 0 / 5 |
| Iceland | 0 / 5 |