correct error “then” → “ten”

[matj1]

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[puredanger]

That is not a typo - you prefix with the base (like 10), then r, as in 16r1A9B

[matj1]

OK, I thought that it means that the base prefix is supposed to be in base ten. Still, I would rather add a comma or a conjunction there for clarity.

prefix with base, then r

[puredanger]

I tweaked a bit, thx