The sum of the series $$(1 + 2) + (1 + 2 + {2^2}) + (1 + 2 + {2^2} + {2^3}) + ....$$ upto $$n$$ terms is
- A$${2^{n + 2}} - n - 4$$
- B$$2({2^n} - 1) - n$$
- C$${2^{n + 1}} - n$$
- D$${2^{n + 1}} - 1$$
✓ Correct answer: A
Want the full step-by-step reasoning?