Count the number of strings of length 11 over the alphabet {a,b,c} subject to each of the following restrictions. 1) The first or the last character is a. 3^11 - (2*3^9*2) 2) The string has exactly 2 a's or exactly 3 b's.

Count the number of strings of length 11 over the alphabet {a,b,c} subject to each of the following restrictions. 1) The first or the last character is a. 3^11 - (23^92) 2) The string has exactly 2 a's or exactly 3 b's.

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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