Ali bin Abu Talib reported,
The Messenger of Allah ﷺ performed the witr prayer, then said, "People of the Quran, perform the witr prayer, for Allah 
is one and loves what is odd in number."
Nasai 1676
Daifأخبرنا هناد بن السري عن أبي بكر بن عياش عن أبي إسحق عن عاصم وهو ابن ضمرة
عن علي رضي الله عنه قال
أوتر رسول الله ﷺ ثم قال يا أهل القرآن أوتروا فإن الله عز وجل وتر يحب الوتر
[Its chain is daif] Tirmidhi narrated it, Prayer, chapter on what has been said that Witr is not obligatory, no. 453, and Ibn Majah, no. 1169, from the hadith of Abu Bakr bin Ayyash, and Abu Dawud, Prayer, chapter on the recommendation of Witr, no. 1416, through another route from Abu Ishaq Sabiie with the same wording. Tirmidhi said, "Hasan." It is also found in Al-Kubra, no. 1384. The hadith has corroborating narrations, see the following hadith.