you communicated wrong. You included 12 and 123. Those are strictly numbers and not parts of sequences of numbers.
If you wanted numbers that began with those digits, then you need to put ellipses after those, as in:
"Assuming strict increase and disallowing 1..., 11..., 12..., 112..., 122..., 123..., and numbers like that with repeats in them."
Next time you can type out the word "sequence" or put in the ellipses so you don't pass on the wrong information.
And no single digit numbers should be included, because they do not consist of numbers where the digits
are increasing from left to right.