Series Sum Calculator
How This Is Calculated
These closed-form formulas — n(n+1)/2 for Σn, n(n+1)(2n+1)/6 for Σn², and [n(n+1)/2]² for Σn³ — are each provable by Mathematical Induction, exactly the technique covered in the Principle of Mathematical Induction chapter guide. Notice Σn³ is literally the square of Σn — a genuinely elegant result.