data/pom/57.xml
<?xml version="1.0" ?>
<math type="pom-exported">
<expression prime-tag="sequence">
<term prime-tag="digit" secondary-tags="numeric">0</term>
<term prime-tag="relation">\rightarrow</term>
<term prime-tag="letter" secondary-tags="Latin">B</term>
<term prime-tag="relation">\rightarrow</term>
<term prime-tag="letter" secondary-tags="Latin">A</term>
<term prime-tag="operation">\oplus</term>
<term prime-tag="letter" secondary-tags="Latin">B</term>
<term prime-tag="relation">\rightarrow</term>
<term prime-tag="letter" secondary-tags="Latin">A</term>
<term prime-tag="relation">\rightarrow</term>
<term prime-tag="digit" secondary-tags="numeric">0</term>
</expression>
</math>