N=int(eval(input()))



ans=0

for a in range(1,N):

  ans += (N-1)//a

  

print(ans)
def main():

  N=int(eval(input()))

  print((sum([(N-1)//a for a in range(1,N)])))

  

if __name__=="__main__":

  main()
N = int(eval(input()))
ans = 0
for a in range(1, N):
    ans += (N - 1) // a
print(ans)

def main():
    N = int(eval(input()))
    print((sum([(N - 1) // a for a in range(1, N)])))


if __name__ == "__main__":
    main()

-N = int(eval(input())) -ans = 0 -for a in range(1, N): -    ans += (N - 1) // a -print(ans) +def main(): +    N = int(eval(input())) +    print((sum([(N - 1) // a for a in range(1, N)]))) + + +if __name__ == "__main__": +    main()