If c0  |–n cn [r] for some n ³ 1, then
 c0  |–+ cn [r] or, simply,  c0  |–+ cn 
If c0  |–n cn [r] for some n ³ 0, then
 c0  |–* cn [r] or, simply, c0  |–* cn
Example: Consider
 apbc |– aqac [1: pb ® qaS], and
 aqac |– acrc  [2: qa ® rcR].
Then,  apbc |–2 acrc [1 2], apbc |–+ acrc [1 2], apbc |–* acrc [1 2]
Sequence of Moves 2/2
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