平均距离

(5n-4)/(3n-1)

1/4(n+1)

K_(m,n)

(2[m^2+n^2+mn+(m+n)])/((m+2)^2)

K_(n,n)

(3n-2)/(2n)

K_(n,n,n)

(2(2n-1))/(3n)

K_(k,m,n)

(2(k^2+m^2+n^2-k-m-n+km+kn+mn))/((k+m+n)^2)

K_n

(n-1)/n

C_n

(2n^2+(-1)^n-1)/(8m)

K^__n

{0   for n=1; infty   otherwise

P_m square P_n

((m+n)(mn-1))/(3mn)

P_n square P_n

(2(n^2-1))/(3n)

P_n square P_n square P_n

((n-1)(n+1))/n

Q_n

1/2n

(2n^2+4n-(-1)^n-3)/(8n)

P_n

((n-1)(n+1))/(3n)

Y_n

(2n^2-4n+(-1)^n-17)/(8(n+2))

S_n

(2(n-1)^2)/(n^2)

W_n

(2(n-2)(n-1))/(n^2)