count = 0
i = 1
while i <= 1000000:
    # print(str(i).startswith('793'))
    # print(str(i % 7 != 0) + '\n')
    if str(i).startswith('793') and i % 7 != 0:
        count = count + 1
        i = i + 1
    else:
        i = i + 1
print(count)