Largest Prime from Consecutive Prime Sum
You are given an integer n.
Return the largest prime number less than or equal to n that can be expressed as the sum of one or more consecutive prime numbers starting from 2. If no such number exists, return 0.
Example 1
Input
n = 20Output
17The prime numbers less than or equal to n = 20 which are consecutive prime sums are 2, 5, and 17, so the largest is 17.
Example 2
Input
n = 2Output
2The only consecutive prime sum less than or equal to 2 is 2 itself.
Constraints
- 1 <= n <= 5 * 10^5