A method for defining sub-problems uses the following recursive formula: $p_i = G_i(p_0, \{p_i, a_i\})$ In this formula, $p_i$ is the i-th sub-problem, $p_0$ is the original problem, $a_i$ is the answer to $p_i$, and $G_i$ is a generation function. What is the most significant implication of this self-referential structure for defining a valid sub-problem?

Evaluating Sub-Problem Validity

Analyzing the Self-Referential Nature of Sub-Problem Generation