Hailstones

"""
Hailstones:
+ Pick some positive integer and call it n.
+ If n is even, divide it by two.
+ If n is odd, multiply it by three and add one.
+ Continue this process until n is equal to one.

I want to write a program that tests every positive integer between 1 and 100.
It should give me:
+ number 
+ amount of steps to reach 1

EXTRA show the results in a scatter plot, using matplotlib.
"""

import random
import matplotlib.pyplot as plt

FIRST_NUMBER_OF_TEST = 1
LAST_NUMBER_OF_TEST = 100

def main():
    x = FIRST_NUMBER_OF_TEST
    list_of_x = [] #keep track of x and steps in two lists
    list_of_steps = []
    for i in range(LAST_NUMBER_OF_TEST):
        n = x #positive integer and call it n
        steps = 0 #will keep track of amount of steps to reach 1
        while n != 1 :
            if n % 2 == 0: #x is an even number
                n = n / 2
                steps = steps + 1
            else : #x is an uneven number
                n = (n * 3) + 1
                steps = steps + 1
        print("for", x, "We need", steps, "to reach 1")
        list_of_x.append(x) #add x to the list
        list_of_steps.append(steps) #add result of steps for x in list
        x = x + 1
    plt.scatter(list_of_x, list_of_steps)
    plt.ylabel('Amount of steps to reach 1')
    plt.show()

if __name__ == "__main__":
    main()