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A combinatorics Problem

  • #1
given a chain of n terms with each term either being x or y, how many arrangements are there such that you don't have any two terms being x next to each other.

for example if n= 5

(x,y,y,y,x) ; (x,y,x,y,x) are acceptable while (y,x,x,y,x) is not acceptable.

Generalize this result for all values of n.
 

Answers and Replies

  • #2
tiny-tim
Science Advisor
Homework Helper
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welcome to pf!

hi physicsmath94! welcome to pf! :wink:

Show us what you've tried, and where you're stuck, and then we'll know how to help! :smile:
 

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