What does this equation mean?

By this article’s classification, this is about as clean a case of vertical, channel-disclosed exposure as currently exists in public: the source, the artifact, the recipient checkpoints, and the training procedure are all named in a peer-reviewed paper, so there is no attribution problem left to solve. A case definition built around a trait specific to R1’s reasoning style — a distinctive self-verification phrasing, a particular pattern of restarting a solution attempt mid-chain — would presumably return a high $T_V$ against any credible convergence baseline, because DeepSeek has already told the field exactly how, and how much, the trait was transferred. That is precisely why this case, on its own, is not a satisfying test of the construction: a discriminator that only succeeds once the transmission channel has already been confessed in a Nature paper adds nothing over reading the Nature paper. The construction earns its keep only on cases where the channel is contested, undisclosed, or actively denied, which is exactly the situation the next case supplies.