n = int(input())
suzu = list(map(int, input().split()))
draw = 0
pt = sum(range(n)) + n
for i in range(n, 1, -1):
    smax = suzu.index(i) + 1
    smax2 = suzu.index(i-1) + 1
    if smax2 <= smax/2:
        draw += smax
        continue
    else:
        pt -= (smax*2 + draw)
        break
print (pt)