Interestingly, I found out if you want to calculate the next number in this series, it works in the following way.

(64 + 1) * 5 = 325

(325 + 1) * 6 = 11742

(11742 + 1) * 7 = 82201

(82201 + 1) * 8 = 657616

(657616 + 1) * 9 = 5918663 which is what I think the number of combinations is if you are allowed any number between 1 and 9 not using any dot more than once.

What I dont understand is the relationship between what logically seems a calculation about primes and the way I found to solve it. And like others have said, this is more about the maths than whether it is a good way to lock a phone

]]>Executive Summary—it all depends. I don’t know for sure, but I used to do a lot of driving on the M1 in the UK, which makes many American roads look just empty, and I tried both strategies at different times, or would simply mentally ‘mark’ a car in…

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