Two mathematicians walk into a bar…

Two mathematicians walk into a bar and decide to play a game to see which one of them can name the biggest number.

“One.” -says the first mathematician.

“Two.”- says the other mathematician.

“Ten.”- comes the response.

“One hundred.” -follows the other one.

“One thousand.” - comes the quick reply.

“One million.” - responds the other.

“One billion!”

At this, the other mathematician ponders for a while, then eventually answers.

“Infinity.” - he says with a smug grin.

For a brief moment they both think the game is over. But then, the other mathematician replies with a cheeky smile.

“Infinity, plus one”.