Problem 628. Book Club

Created by @bmtran (Bryant Tran)

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Last Solution submitted on Dec 29, 2018

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Venu Lolla on 27 Apr 2012

@bmtran, could you please specify the problem to a greater detail? Are there any constraints such as: each member should read at least one book? Do permutations of who reads which book matter? Cheers, VL.

Bart Vandewoestyne on 27 Apr 2012

Same for me... i'm not sure if I understand the problem correctly... If my combinatorics is right, the solution should simply be factorial(k)/factorial(k-n) but apparently this is not the case... I assume I'm misinterpreting something???

@bmtran (Bryant Tran) on 28 Apr 2012

sorry if i wasn't clear enough. i'm revising my question to be more specific now

J. S. Kowontan on 30 Jun 2018

Mathematical Reformulation: How many K-letter words can be formed using N-letters if repetition of letters is allowed and each letter appears at least once?....Hint: A closed form solution exist aside the brute force solutions.

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Problem 628. Book Club

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