1. The problem asks to find the sum $S_4$ of the first 4 terms of a sequence, where each term is the sum of all previous partial sums. 2. Let's denote the terms of the sequence as $a_1, a_2, a_3, a_4$ and the partial sums as $S_1, S_2, S_3, S_4$ where $S_n = a_1 + a_2 + \cdots + a_n$. 3. Given that each term $a_n$ is the sum of all previous partial sums, we have: $$a_1 = S_0 = 0 \quad \text{(assuming $S_0=0$ for the first term)}$$ $$a_2 = S_1 = a_1$$ $$a_3 = S_1 + S_2 = a_1 + (a_1 + a_2)$$ $$a_4 = S_1 + S_2 + S_3 = a_1 + (a_1 + a_2) + (a_1 + a_2 + a_3)$$ 4. Calculate each term step-by-step: - $a_1 = 0$ - $a_2 = a_1 = 0$ - $a_3 = a_1 + a_1 + a_2 = 0 + 0 + 0 = 0$ - $a_4 = a_1 + a_1 + a_2 + a_1 + a_2 + a_3 = 0 + 0 + 0 + 0 + 0 + 0 = 0$ 5. Therefore, all terms are zero, so the sum $S_4 = a_1 + a_2 + a_3 + a_4 = 0$. 6. If the initial term $a_1$ is not zero, please provide its value to proceed with the calculation.