N=int(input())
G=[[] for i in range(N)]
for i in range(N-1):
    a,b=map(int,input().split())
    G[a-1].append(b-1)
    G[b-1].append(a-1)
from collections import deque
S=deque()
dist=[-1]*N
dist[0]=0
S.append(0)
while S:
    x=S.pop()
    for y in G[x]:
        if dist[y]>=0:
            continue
        dist[y]=dist[x]+1
        S.append(y)
T=[{} for i in range(N)]
L=[]
for i in range(N):
    L.append((dist[i],i))
dp=[0]*N
L.sort(reverse=True)
for i in range(N):
    x=L[i][1]
    w=0
    for y in G[x]:
        if dist[y]<dist[x]:
            continue
        w=max(dp[y]+1,w)
        T[x][y]=dp[y]
    dp[x]=w
S=deque()
S.append(0)
while S:
    x=S.pop()
    m=len(G[x])
    l=[0]*m
    r=[0]*m
    for i in range(m):
        y=G[x][i]
        d=T[x][y]
        l[i]=d
        r[i]=d
    for i in range(1,m):
        l[i]=max(l[i-1],l[i])
    for i in range(m-2,-1,-1):
        r[i]=max(r[i],r[i+1])
    for i in range(m):
        y=G[x][i]
        if dist[y]<dist[x]:
            continue
        w=0
        if i>0:
            w=max(w,l[i-1]+1)
        if i<m-1:
            w=max(w,r[i+1]+1)
        T[y][x]=w
        S.append(y)
result=0
for i in range(N):
    l=[]
    for j in G[i]:
        l.append(T[i][j]+1)
    l.sort(reverse=True)
    for m in range(len(G[i])):
        x=l[m]
        count=x*(m+1)+1
        result=max(result,count)
print(result)