Does there exist an undirected graph with 99 vertices, in which each two adjacent vertices have
exactly one common neighbor, and in which each two non-adjacent vertices have exactly two common
neighbors?
Equivalently, every edge should be part of a unique triangle and every non-adjacent pair should be
one of the two diagonals of a unique 4-cycle.
The first condition is equivalent to being locally linear.
Actions
Submit a Proof
Have a proof attempt? Submit it for zero-trust verification.
