# Revision history [back]

I guess it is not onlt a matter of the server restarting or not. Since the shortlink is identified with 6-letter lower-case chararacters, with high probability you will get a collision after 20000.

Regarding youtube, i do not have a youtube account so i can not try by myself, but i bet the culprit is the &, which is used to separate variables sent to the server. SInce only the first variable (named z) seems absolutely necessary, you can try by removing what remains, that is trnasform

https://sagecell.sagemath.org/?z=eJxLyU9JTU7MSE0pys_T0AQAKYsFMg==&lang=sage&interacts=eJyLjgUAARUAuQ==


into

https://sagecell.sagemath.org/?z=eJxLyU9JTU7MSE0pys_T0AQAKYsFMg==


I guess it is not onlt a matter of the server restarting or not. Since the shortlink is identified with 6-letter lower-case chararacters, with high probability you will get a collision after 20000.

Regarding youtube, i do not have a youtube account so i can not try by myself, but i bet the culprit is the &, which is used to separate variables sent to the server. SInce only the first variable (named z) seems absolutely necessary, you can try by removing what remains, that is trnasform

https://sagecell.sagemath.org/?z=eJxLyU9JTU7MSE0pys_T0AQAKYsFMg==&lang=sage&interacts=eJyLjgUAARUAuQ==


into

https://sagecell.sagemath.org/?z=eJxLyU9JTU7MSE0pys_T0AQAKYsFMg==


In case they are the culprit, you can even remove the trailing = that are used for padding:

https://sagecell.sagemath.org/?z=eJxLyU9JTU7MSE0pys_T0AQAKYsFMg


I guess it is not onlt a matter of the server restarting or not. Since the shortlink is identified with 6-letter lower-case chararacters, with high probability you will get a collision after 20000.20000 (birthday paradox).

Regarding youtube, i do not have a youtube account so i can not try by myself, but i bet the culprit is the &, which is used to separate variables sent to the server. SInce only the first variable (named z) seems absolutely necessary, you can try by removing what remains, that is trnasform

https://sagecell.sagemath.org/?z=eJxLyU9JTU7MSE0pys_T0AQAKYsFMg==&lang=sage&interacts=eJyLjgUAARUAuQ==


into

https://sagecell.sagemath.org/?z=eJxLyU9JTU7MSE0pys_T0AQAKYsFMg==


In case they are the culprit, you can even remove the trailing = that are used for padding:

https://sagecell.sagemath.org/?z=eJxLyU9JTU7MSE0pys_T0AQAKYsFMg