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2018 AIME II Question 11

AIME · 2018 AIME II

Question 11

Find the number of permutations of $1,$ $2,$ $3,$ $4,$ $5,$ $6$ such that for each $k$ with $1 \le k \le 5,$ at least one of the first $k$ terms of the permutation is greater than $k.$