The Messenger of Allah ﷺ allotted on the day of Khaybar two shares for the horseman and one share for the foot soldier.Nafi explained this, saying, "If a man had a horse with him, he received three shares, and if he had no horse, he received one share."
قسم رسول الله ﷺ يوم خيبر للفرس سهمين، وللراجل سهما. قال: فسره نافع فقال: إذا كان مع الرجل فرس فله ثلاثة أسهم، فإن لم يكن فرس فله. سهم.
Bukhari narrated it in the Book of Military Expeditions (4228), and Muslim in the Book of Jihad and Expeditions, where he said, then he mentioned it. (57:1762) Both narrated it through Ubaydullah bin Umar, from Nafi, from Ibn Umar, and the wording given is Bukhari's. Muslim's version does not include Ubaydullah's statement.