What are the Java semantics of an escaped number in a character literal=?iso-8859-1?Q?=2C_e.g._'\15'_=3F_=96_stackoverflow.com?=

What are the Java semantics of an escaped number in a character literal,
e.g. '\15' ? – stackoverflow.com

Please explain what, exactly, happens when the following sections of code
are executed: int a='\15'; System.out.println(a); this prints out 13; int
a='\25'; System.out.println(a); this prints …