R(k,l)the smallest integer satisfying: if n=R(k,D),for any 2-coloring of Kn, there exists a red Kk or a blue Ki. 2-coloring of K r:(）,(rod.bine) Ramsey Theorem R(k,l)is finite. Frank P.Ramsey (1903-1930) R(3,3)=6R(k,l) the smallest integer satisfying: ￾ Ramsey Theorem R(k,l) is finite. 2-coloring of Kn f : ￾[n] 2 ⇥ ￾ {red, blue} if n≥ R(k,l), for any 2-coloring of Kn, there exists a red Kk or a blue Kl. R(3,3) = 6 Frank P. Ramsey (1903-1930)