This is actually possible to do if you have the number pad on the right of the keyboard. You can type the numbers 1-9 by sliding your finger across the number keys on the normal keyboard and the 2 digit numbers can be typed on the number pad.
It's pretty easy with two hands, one on the num pad and the other doing the other number keys. Trying to do it one-handed on the num pad is a real challenge. I am getting up to around 46 or 47 one-handed. Fun quiz
This really is impossible because when typing single digit numbers it doesn't clear. So for example typing 1,2,3,4,5,6 it accepts 1 then 12, leaving 2 blank, then 23, 34, 45 and 56 at which point it becomes a rolling log jam.
Yes. I did it with ∞ left by doing it untimed.
http://gyazo.com/95cc0df341960ffd4172cae87be3828f
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