This is a good and authentic hadith. It is also narrated on the authority of Abu Hurayrah, from the Prophet, peace and blessings be upon him, that he said: "Indeed, I seek forgiveness from Allah one hundred times a day." It was narrated by Muhammad ibn 'Amr, from Abu Salamah, from Abu Hurayrah (1). It has also been narrated through multiple chains from the Prophet, peace and blessings be upon him: "Indeed, I seek forgiveness from Allah one hundred times a day" (2).

3542 - 'Abd ibn Humayd narrated to us, he said: 'Abd al-Razzaq informed us, he said: A shaykh from the people of Madinah informed us, from al-'Ala' ibn 'Abd al-Rahman, from his father, from Abu Hurayrah, who said: The Messenger of Allah, peace and blessings be upon him, recited this verse one day: {And if you turn away, He will replace you with another people, then they will not be like you} [Muhammad: 38]. They said: Who will replace us? He said: Then the Messenger of Allah, peace and blessings be upon him, struck the shoulder of Salman, and then said: "This one and his people, this one and his people" (3).

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(1) Authentic. It was narrated by Ibn Majah (3815) and al-Nasa'i in "'Amal al-Yawm wa al-Laylah" (434). It is in "al-Musnad" (9807).
(2) From his statement: "It has also been narrated through multiple chains" to here is an addition from (S).
(3) Authentic, but this chain is weak. The shaykh from Madinah is 'Abdullah ibn Ja'far, as will be mentioned by name in the following narration, and he is weak. It was also narrated by Abu Nu'aym in "Ta'rikh Asbahan" 1/3, and al-Bayhaqi in "al-Dala'il" 6/334, through multiple paths from 'Abdullah ibn Ja'far ibn Najih, with this chain. 'Abdullah ibn Ja'far was omitted from the printed edition of "al-Dala'il," so it should be corrected from here. It was also narrated by al-Tabari in "al-Tafsir" 26/66 and 67, Ibn Hibban (7123), and Abu Nu'aym =