Call a positive integer monotonous if it is a one-digit number or its digits, when read from left to right, form either a strictly increasing or a strictly decreasing sequence. For example, 3, 23578, and 987620 are monotonous, but 88, 7434, and 23557 are not. How many monotonous positive integers are there?<spanclass=′latex−bold′>(A)</span> 1024<spanclass=′latex−bold′>(B)</span> 1524<spanclass=′latex−bold′>(C)</span> 1533<spanclass=′latex−bold′>(D)</span> 1536<spanclass=′latex−bold′>(E)</span> 2048