import bisect
n=int(input())
a=list(map(int,input().split()))
b=[[]for i in range(500)]
for i in range(n):
	b[a[i]-1].append(i)
for i in range(500):
	b[i].sort()
d=[]
for i in range(500):
	e=[0]
	for j in b[i]:
		e.append(e[-1]+j)
	d.append(e)
c=0
for i in range(499):
	y=len(b[i])
	for j in range(i+1,500):
		for k in b[j]:
			x=bisect.bisect(b[i],k)
			c+=2*(j-i)*(x*k-d[i][x]+d[i][-1]-d[i][x]-(y-x)*k)
print(c)