2018 UNM-PNM Statewide High School Mathematics Contest II Problems/Problem 3

Problem

Let $a_1 < a_2 < a_3$ be three positive integers in the interval $[1,14]$ satisfying $a_2-a_1>=3$ and $a_3-a_2>=3$. How many different choices of $(a_1,a_2,a_3)$ exist?


Solution

See also

2018 UNM-PNM Contest II (ProblemsAnswer KeyResources)
Preceded by
Problem 2
Followed by
Problem 4
1 2 3 4 5 6 7 8 9 10
All UNM-PNM Problems and Solutions
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