Find the total number of `n` -digit number `(n >1)` having property that no two consecutive digits are same.

The number of 'n' digit numbers such that no two consecutive digits are same is

The number of three-digit numbers having only two consecutive digits identical is

Find the total number of 9-digit numbers which have all different digits.

The number of 5-digit numbers in which no two consecutive digits are identical, is

The number of three digit numbers having only two consecutive digits identical is

The total number of 9-digit number which have all different digits is

Let a_(n) denote the number of all n-digit numbers formed by the digits 0,1 or both such that no consecutive digits in them are 0. Let b_(n) be the number of such n-digit integers ending with digit 1 and let c_(n) be the number of such n-digit integers ending with digit 0. Which of the following is correct ?