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Let U = {1, 2,...,n}, where n is a large positive integer greater than 1000. Let k be a positive integer less than n. Let A, B be subsets of U with |A| = |B| = k and A ∩ B = ∅. We say that a permutation of U separates A from B if one of the following is true.
All members of A appear in the permutation before any of the members of B.
All members of B appear in the permutation before any of the members of A.
How many permutations of U separate A from B?
I want to buy a laptop. As I don't know much about laptops please do suggest some laptops. My budget is 45-48 thousands indian rupees. Well I have searched online and I am confused between hp 14s-fq1092au and lenovo ideapad 3 82ku017kin Which one is better. Or is there any other laptop laptop which I should consider checking before buying.
I know this is not the right place for the post but you guys know too much about these things so please suggest something.
