Write a program that fills in an array, a, of 25 integers where each element contains the sum of all the previous elements plus 1, e.g., a[0] is 1 and a[3] is equal to a[0] + a[1] + a[2] + 1. Then use a loop to print out every 3rd element of the array starting at a[24], so a[24], a[21], a[18]..., a[0]. Your output should look exactly like this: 24: 16777216 21: 2097152 18: 262144 15: 32768 12: 4096 9: 512 6: 64 3: 8 0: 1