Converting a number from base 10 to any base is a matter of finding the largest powers of that contains. However many copies of this power of are needed is equal to the leading digit of in base . Then keep doing this with the remainder terms as needed.
In this case,
23 = 16 + 7 = 2*8^1 + 7
so the first digit of 23 in base 8 is 2. The remainder 7 contains no powers of 8, so we're done; the last digit is this remainder, and we write
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