"O Messenger of Allah, what do you think I should say in my supplication, if I come upon Laylatul-Qadr?" He said: "Say: 'Allahumma innaka 'afuwwun tuhibbul-'afwa, fa'fu 'anni (O Allah, You are Forgiving and love forgiveness, so forgive me).'" (Using translation from Ibn Mājah 3850)   

يَا رَسُولَ اللهِ إِنْ وَافَقْتُ لَيْلَةَ الْقَدْرِ فَبِمَ أَدْعُو؟ قَالَ قُولِي اللهُمَّ إِنَّكَ عَفُوٌّ تُحِبُّ الْعَفْوَ فَاعْفُ عَنِّي  

"O Messenger of Allah, what do you think I should say in my supplication, if I come upon Laylatul-Qadr?" He said: "Say: 'Allahumma innaka 'afuwwun tuhibbul-'afwa, fa'fu 'anni (O Allah, You are Forgiving and love forgiveness, so forgive me).'" (Using translation from Ibn Mājah 3850)   

عَائِشَةُ يَا رَسُولَ اللهِ إِنْ وَافَقْتُ لَيْلَةَ الْقَدْرِ بِمَ أَدْعُو؟ قَالَ قُولِي اللهُمَّ إِنَّكَ عَفُوٌّ تُحِبُّ الْعَفْوَ فَاعْفُ عَنِّي