Very nice approach ! But it does not work when in the first any sign part is a "x" 
"x1x2x...x"   # should be valid is x.{3}3x.{3}x,   but is NOK OK

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In reply to Re^2: Regular Expression: search two times for the same number of any signs by Anonymous Monk
in thread Regular Expression: search two times for the same number of any signs by Anonymous Monk

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