摘要：Let P=(p_1, p_2, ..., p_n) be a polygonal chain. The stretch factor of P is the ratio between the total length of P and the distance of its endpoints, sum_{i = 1}^{n-1} p_i p_{i+1} / p_1 p_n . For a parameter c >= 1, we call P a c-chain if p_ip_j + p_jp_k <= c p_ip_k , for every triple (i,j,k), 1 <= i
关键词：polygonal chain; vertex dilation; Koch curve; recursive construction
