The Prophet ﷺ as saying: Seek laitat al-Qadr in the last ten night of Ramadan. When nine (nights) remain (i.e. on the twenty first) , when seven (night) remain (i.e. on the twenty third), and when five (nights) remain (i.e. on the twenty fifth).
عَنِ النَّبِيِّ ﷺ قَالَ الْتَمِسُوهَا فِي الْعَشْرِ الأَوَاخِرِ مِنْ رَمَضَانَ فِي تَاسِعَةٍ تَبْقَى وَفِي سَابِعَةٍ تَبْقَى وَفِي خَامِسَةٍ تَبْقَى