1. Pascal's Triangle is a triangular arrangement of integers that have many interesting mathematical properties. Although it is usually associated with the French mathematician Blaise Pascal, the triangle was actually described centuries earlier by the Chinese mathematician Yang Hui and the Persian astronomer and poet Omar Khayyam. Pascal's Triangle is usually represented in the following form: sah (s) 1 1 1 6 1 5 1 4 15 1 3 10 1 2 6 20 1 3 10 1 4 1 1 5 15 6 1 1 Notice that each entry is the sum of the two nearest entries in the row above (one to the left and one to the right), assuming that a position with no entry has the value zero. Write Java code that asks the user to enter an integer between 1 and 20, and then calculates and displays that number of rows of Pascal's Triangle. For convenience, you may prefer to display the values in an alternative form such as