The Sherlock Holmes Problem Solving Challenge - Week 4

Date: 23rd Nov 2018 @ 8:20pm

Can you work out this four-digit number that has a great significance to Sherlock?

No digit is allowed to repeat in the code. If each blue dot indicates that a digit in the corresponding row is both of the correct value and in the correct position, and a brown dot indicates that a digit is correct but not in the correct position, what is the four digit number, and can you tell me why it is significant?