How many strings of length 9 over the alphabet {a, b, c} are there which contain at least seven consecutive a’s? Hint: Upon writing down a few such strings you will notice that they must take one of three distinct forms (depending on where the consecutive a’s are). Then use the inclusion–exclusion principle.

How many strings of length 9 over the alphabet {a, b, c} are there which contain at least seven consecutive a’s? Hint: Upon writing down a few such strings you will notice that they must take one of three distinct forms (depending on where the consecutive a’s are). Then use the inclusion–exclusion principle.

Elements Of Modern Algebra

8th Edition

ISBN:9781285463230

Author:Gilbert, Linda, Jimmie

Publisher:Gilbert, Linda, Jimmie

Chapter1: Fundamentals

Section1.2: Mappings

Problem 21E: In Exercises 20-22, Suppose and are positive integers, is a set with elements, and is a set...

See similar textbooks