The mathematical formula to find the sum of 1²+2²+3²+….+n² is n(n+1)(2n+1)/6
So to find the sum of series we use this formula.
n = int(input("Enter Positive Number : "))
sum = 0
sum= (n*(n+1)*(2*n + 1))/6
print("The Sum of Series is",sum)
Enter Positive Number : 5
The Sum of Series is 55.0