Sharpsign O
#O
rational reads rational in octal (radix 8).
For example,
#o37/15 ≡ 31/13
#o777 ≡ 511
#o105 ≡ 69 ;105_8
The consequences are undefined if the token immediately following
the #O
does not have the syntax of an octal (i.e., radix 8) rational.