Any five points in the plane contain a convex quadrilateral according to this person’s so-called “happy ending problem.” (15[1])The Green-Tao (15[1])theorem proves a specific case of a conjecture (-5[1])named after this person, (15[1]-5[2])which states that any substantial set has arbitrarily long (15[1])arithmetic progressions. (15[1]-5[1])This person is the alphabetically first namesake of a model used to generate random graphs (15[2])given (15[1])a fixed (15[1]-5[1])number (15[1])of (15[1])nodes and edges. (15[2])Along with George (*) Szekeres (“SEK-eh-resh”), this man (10[1])proved (10[1])the first upper bound for Ramsey (10[1])numbers. This man popularized a technique which proves the existence of objects by showing the chance of choosing them randomly is nonzero called the probabilistic method. For 10 points, name this eccentric Hungarian mathematician (10[3]-5[1])whose (10[1])namesake “number” quantifies distance (10[1])from him via coauthorship of papers. ■END■ (10[4])