I'm looking at a paper (On Base and Turyn Sequences by C. Koukouvinos, S. Kounias and K. Sotirakoglou) that describes an algorithm for finding specific sequences. Part of the algorithm involves finding an intermediary sequence $k$ of length $m$, $m < n$, where $n + 1$ is the length of the final sequence, and summing elements $k_1$ and $k_{n+1}$ then checking congruence. The problem is that $k$ is shorter than $n + 1$ (in some cases, much shorter). I don't think it's a typo in the paper ((33) on page 831 if you're curious), and from experimenting I don't think $n+1$ % $m$ is correct. Does anyone know what this means?
Thanks!