AION
Research paperEfficiency & Inference1 source · Oct 7, 2026

YANchor-4B: Effective Long-Horizon Reasoning in O(N) Time with O(1) Memory

Therefore, we present YANchor-4B, a general-purpose recurrent model that preserves crucial memory as ANchors for retrieval during subsequent reasoning.

Key points

  • Long-horizon reasoning demands access to earlier information at a manageable generation cost.
  • Full-history attention incurs growing storage and computation, while recurrent compression can lose precise details.
  • Beyond $O(N)$-time generation and $O(1)$ memory, YANchor enables effective long-horizon reasoning through its multidimensional memory mechanism.
  • For example, on challenging math problems, it achieves 82.93% mean pass@1 on AIME 2024--2026 and 63.64% on HMMT, substantially outperforming linear-time, constant-state counterparts, including larger models.

Sources (1)

  • [1]YANchor-4B: Effective Long-Horizon Reasoning in O(N) Time with O(1) Memory
    arXiv (AI, ML, NLP, CV, robotics, multi-agent) · Oct 7, 02:03 PM
    Therefore, we present YANchor-4B, a general-purpose recurrent model that preserves crucial memory as ANchors for retrieval during subsequent reasoning.
    Long-horizon reasoning demands access to earlier information at a manageable generation cost.

Extractive summary: sentences quoted from the sources.