"I think it would surprise you how good it would sound, me and Cee Lo together," Shelton says.
The actress was taken to Sherman Oaks Hospital following a medical emergency on Monday night.
After the show, his father Paul tweeted, "WOW! @nickjonas was amazing tonight.My heart is full."
"I'm going to the Super Bowl this year to see my group LMFAO perform with Madonna," will.i.am says.
The musician was detained by police on Saturday following an alleged argument with his girlfriend.