random / 2015-04-13 14:07

In the book *Discrete Wiskunde* by J. H. van Lint and J. W. Nienhuys, I found something interesting about how student identity numbers are formed at the TU/e (my university). According to this book, a student number of the form $a_0 \, a_1 \, a_2 \, a_3 \, a_4 \, a_5$ is valid iff

is divisible by $10$. (Note that the book is rather old, and current identity numbers are written with an additional zero in front of them.)

I made a small tool to check a student number. (Leave out the zero in the beginning; the script expects a 6-digit input.)