infile = open("DATA2.txt","r")
outfile = open("OUT2.txt","w")

for run in range(0,5):
    used = []
    works = 0
    number = int(infile.readline())
    for l in range(1,number+1):
        for h in range(1,number + 1):
            result = l * h
            if result <= number:
                works += 1
    works = works /2 + 1
    outfile.write(str(works)+"\n")
    
outfile.close()
infile.close()