Hello, please provide a step-by-step solution, thanks.

Question 2: Sum of a Series (4 points) The value of (12 + 22 + ... + n)" is always greater than 1/3 for any n >1 and as n grows, the value gets closer to 1/3. Write a Python function onethird (n) that returns a floating-point number which reproduces this formula. In [ ]: def onethird(n): return ans # Your Provided Sample Test Cases print("#1", onethird(1) == 1.0) print("#2", round (onethird (3), 6) == 0.518519) print("#3", round (onethird (5), 6) == 0.44)