Discrete Mathematics Level pending

Find the number of permutations (p1 , p2 , p3 , p4 , p5 , p6) of 1 , 2 , 3 , 4 , 5 , 6 such that for any k , 1<=k<=5, (p1 , p2 , . ........ , pk) is not a permutation of (1,2,3,........,k), i.e. p1 not equal to 1, (p1 , p2) is not a permutation of (1,2) , (p1 , p2 , p3) is not a permutation of (1,2,3) etc.

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