2396. Strictly Palindromic Number
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An integer n is strictly palindromic if, for every base b between 2 and n - 2 (inclusive), the string representation of the integer n in base b is palindromic.
Given an integer n, return true if n is strictly palindromic and false otherwise.
A string is palindromic if it reads the same forward and backward.
Example 1:
Input: n = 9 Output: false Explanation: In base 2: 9 = 1001 (base 2), which is palindromic. In base 3: 9 = 100 (base 3), which is not palindromic. Therefore, 9 is not strictly palindromic so we return false. Note that in bases 4, 5, 6, and 7, n = 9 is also not palindromic.
Example 2:
Input: n = 4 Output: false Explanation: We only consider base 2: 4 = 100 (base 2), which is not palindromic. Therefore, we return false.
Constraints:
4 <= n <= 105
Hints
Hint 1
Consider the representation of the given number in the base n - 2.
Hint 2
The number n in base (n - 2) is always 12, which is not palindromic.