利用嵌入联树模型和组合计数的相关方法,获得了由鹅卵石路图添加一条边所得到的一类图G。在球面及射影平面上的嵌入个数,它们分别为2n-1(n≥2)和(3n-3)2n-1(n≥2).
By the model of joint tree and combinatorial method, the number of embedding on the sphere and projective plane of graph Gn, which is obtained by adding an edge to the cobblestone path, is obtained. They are 2n-1(n≥2) and (3n-3)2n-1(n≥2), respectirely.