title: regex to check a number with format ab0ab0
body: <p>I'm trying to write a regular expression in oracle that match the following number format :
  ab0ab0 where b can be strictly equal to a-1 or a+1</p>
  
  <p>but I'm having difficulties with increasing or decreasing a digit value in regex.</p>
  
  <p>I don't want to add all possible values in the regular expression with alternation.</p>
  
  <p>what I'm done so far is : ^(\d)(\d)0\1\2(0)$
  but it doesn't check if b=a-1 or a+1</p>