Shorter but not Worse: Frugal Reasoning via Easy Samples as Length Regularizers in Math RLVR. - Abdelaziz Bounhar; Hadi Abdine; Evan Dufraisse; Ahmad Chamma; Amr Mohamed 005; Dani Bouch; Michalis Vazirgiannis; Guokan Shang (CoRR, 2025)