MathDB
2013 called and they want their graph theory back

Source: 2023 IRN-SGP-TWN Friendly Math Competition P4

July 16, 2023
graph theorycombinatorics

Problem Statement

On a connected graph GG, one may perform the following operations:
[*]choose a vertice vv, and add a vertice vv' such that vv' is connected to vv and all of its neighbours [*] choose a vertice vv with odd degree and delete it
Show that for any connected graph GG, we may perform a finite number of operations such that the resulting graph is a clique.
Proposed by idonthaveanaopsaccount