You may not believe this, but you are in fact a mind reader.
It is true and I'm going to prove it to you... you are going to read my mind...
We are both going to think of a 4 digit number, with one rule, there must be at least 2 unique digits present (so you could not use 1111, but 1112 would be fine). But make it fun... don't use 1112.
Write down your 4 digit number... Our numbers do not match... it's not that simple.
Now write the same digits in decending order, then in ascending order. So if your number was 3527, write 7532, then 2357. Next, subtract the ascending number from the descending. This gives you a new 4 digit number.
What I want you to do it keep repeating this until you think you have got to the same number I have thought of... or to put it another way... until you have read my mind.
Finally, put MY 4 digit number into certitude... this will tell you where the cache is hidden.
You can validate your puzzle solution with
certitude.