Question 1
Find the largest positive integer $n$ such that for every prime $p$ with $2\lt p\lt n$, the number $n-p$ is prime. (4 points)
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Practice scoring adds all whole-question scores (maximum 60). Official ITOT scoring adds only the three highest whole-question scores (maximum 32), after summing subparts within each question. The importer does not enforce best-three scoring. Duration: 300 minutes from historical organizer general rules, not an individually printed duration on this paper.
Neutral editorial illustration.
Practice scoring adds all whole-question scores (maximum 60). Official ITOT scoring adds only the three highest whole-question scores (maximum 32), after summing subparts within each question. The importer does not enforce best-three scoring. Duration: 300 minutes from historical organizer general rules, not an individually printed duration on this paper.