A pentagonal number is defined as n(3n−1) ∕ 2 for n = 1, 2, . . ., etc.. Therefore, the first few numbers are 1, 5, 12, 22, XXXXXXXXXXWrite a method with the following header that returns a pentagonal...

A pentagonal number is defined as n(3n−1) ∕ 2 for n = 1, 2, . . ., etc.. Therefore, the first few numbers are 1, 5, 12, 22, . . . . Write a method with the following header that returns a pentagonal number:
public static int getPentagonalNumber(int n)

For example, getPentagonalNumber(1) returns 1 and getPentagonalNumber(2) returns 5. In Java, Write a test program that uses this method to display the first 100 pentagonal numbers with 10 numbers on each line. Numbers are separated by exactly one space.