Let $a_1, \dots, a_p$ be (not necessarily distinct) residues modulo a prime $p$, such that there exists some $r$ so that if $S \subseteq [p]$ is non-empty and $$\sum_{i \in S} a_i \equiv 0 \pmod{p}$$ then $|S| = r$.

How a contribution reaches this record

Seven steps, in four places.

1. 1

   Read the sources and their formal declarations.

   Public
2. 2

   Work on it, wherever you work.

   Your machine
3. 3

   Keep an Approach and its Attempts here.

   Needs an account
4. 4

   Attach evidence by its content root.

   Needs an account
5. 5

   Prepare an unsigned Submission draft.

   Needs an account
6. 6

   Sign it with your own key.

   Your machine
7. 7

   The Repository decides.

   The Repository