n = int(input())

zenbu = n * (n + 1) / 2

A = (sum(i for i in range(1, n + 1) if i % 3 == 0))
B = (sum(i for i in range(1, n + 1) if i % 5 == 0))
C = (sum(i for i in range(1, n + 1) if i % 15 == 0))

D = zenbu - A - B + C

print(int(D))