The Prophet (ﷺ) used to say when throwing pebbles in three jamarat:
اَللَّهُ أَكْبَرُ
Pronunciation
Allahu 'Akbar
Meaning
Allah is the Most Great. Then he would move forward a little and stand facing the Qibla and would do Dua with both hands raised in the first Jamra and the second Jamra. But at the time of throwing every pebble at Jamratul Akbaba, he would say ‘Allahu Akbar’ and return without staying there.
Source: Bukhari: 1751
Read the hadith
حَدَّثَنَا عُثْمَانُ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا طَلْحَةُ بْنُ يَحْيَى، حَدَّثَنَا يُونُسُ، عَنِ الزُّهْرِيِّ، عَنْ سَالِمٍ، عَنِ ابْنِ عُمَرَ ـ رضى الله عنهما ـ أَنَّهُ كَانَ يَرْمِي الْجَمْرَةَ الدُّنْيَا بِسَبْعِ حَصَيَاتٍ، يُكَبِّرُ عَلَى إِثْرِ كُلِّ حَصَاةٍ، ثُمَّ يَتَقَدَّمُ حَتَّى يُسْهِلَ فَيَقُومَ مُسْتَقْبِلَ الْقِبْلَةِ فَيَقُومُ طَوِيلاً، وَيَدْعُو وَيَرْفَعُ يَدَيْهِ، ثُمَّ يَرْمِي الْوُسْطَى، ثُمَّ يَأْخُذُ ذَاتَ الشِّمَالِ فَيَسْتَهِلُ وَيَقُومُ مُسْتَقْبِلَ الْقِبْلَةِ فَيَقُومُ طَوِيلاً وَيَدْعُو وَيَرْفَعُ يَدَيْهِ، وَيَقُومُ طَوِيلاً، ثُمَّ يَرْمِي جَمْرَةَ ذَاتِ الْعَقَبَةِ مِنْ بَطْنِ الْوَادِي، وَلاَ يَقِفُ عِنْدَهَا ثُمَّ يَنْصَرِفُ فَيَقُولُ هَكَذَا رَأَيْتُ النَّبِيَّ صلى الله عليه وسلم يَفْعَلُهُ.
Narrated Salim: Ibn `Umar used to do Rami of the Jamrat-ud-Dunya (the Jamra near to the Khaif mosque) with seven small stones and used to recite Takbir on throwing every pebble. He then would go ahead till he reached the level ground where he would stand facing the Qibla for a long time to invoke (Allah) while raising his hands (while invoking). Then he would do Rami of the Jamrat-ul-Wusta (middle Jamra) and then he would go to the left towards the middle ground, where he would stand facing the Qibla. He would remain standing there for a long period to invoke (Allah) while raising his hands, and would stand there for a long period. Then he would do Rami of the Jamrat-ul-Aqaba from the middle of the valley, but he would not stay by it, and then he would leave and say, "I saw the Prophet (ﷺ) doing like this." [Bukhari: 1751]
Duas from IslamicAPI's Masnun Dua dataset (based on the Quran, hadith, Hisnul Muslim and Rahe Belayat). See the dataset