Assalaamu alaikum,

Alhamdulillah, I forgot the transliteration for the du'aas in the text. Here it is.
The Adhkaar between the Two Sajdahs 
In this sitting, he (sallallaahu 'alaihi wa sallam) would say: 
  1.. 


  Allahumma Rabbi ighfirli, warhamnee, wajburnee, warzuqnee, warfa'nee, wahdinee, wa 'aafinee, warzuqnee.
  O Allaah! (in one version: O my Lord!) Forgive me; have mercy on me; [strengthen me;] [raise my rank;] guide me; [pardon me;] sustain me.156
  Or sometimes, he would say:


  2.. 


  Rabbighfirli Ighfirli
  O my Lord! Forgive me, forgive me.157

He would say the above two in night prayer also.158 

Allahumma salli wasallim alaa Nabiyyina Muhammad. Wasalaam.
Modou Mbye