[avodonosov]

Thank you very much. I like the equation over time.

Your explanation is difficult to follow when you do distributivity of % over +. I mean when you move from

    (i + t) % n = (j + 2t) % n

to

    (i % n) + (t % n) = (j % n) + (2t % n)

Here I read the '=' as normal number equality. A simplified example to demostrate that distributivity is not valid here:

    (5 + x) % 3 = 4
    5 % 3 + x % 3 = 4

In the second line x=5 is a solution. But in the first line x is not a solution.

It's better to express your explanation using "= (mod n)" from the beginning.

    (i + t) % n = (j + 2t) % n 
    i + t = j + 2t (mod n)