Dark room of treasure or doomLogic Level 5
A dark room full of valuable orbs with superpowers : 1 orb inscribed 1, 2 orbs inscribed 2, ... , 50 orbs inscribed 50 on them [orbs inscribed 1 to 50 on them, with orb numbers respectively 1 to 50].
As soon as Jason Langdon entered the room, the lights turned out and the door got close. A genie asked Jason Langdon to pick at least 10 orbs with the same integer inscribed on them.
If he did so, he would get all orbs of that room. If he failed, he'd be stuck in this room forever.
Additionaly, the genie told him that for each orb he picked, he will remain asleep for a day at the middle of nowhere. JL didn't want to lose an extra day of his life, but he didn't wish to get stuck either.
In this dark room where a man can never determine which orb is being picked, what's the least number of orbs JL should pick, to remain safe and to win all those orbs?