// Eliminar caracteres que no son números ni signos matemáticos, y separar lo demás en un array
// https://es.stackoverflow.com/q/64125/127
using System;
using System.Text.RegularExpressions;
 
public class Test
{
	public static void Main()
	{	
	    string patron = @"(?:- *)?\d+(?:\.\d+)?";
	    string operacion = "(2/3x^2/3) * (1/4X^-1/2)";
	    Regex regex = new Regex(patron);
 
        foreach (Match m in regex.Matches(operacion))
        {
            Console.WriteLine("Número: {0}", m.Value);
        }
	}
}

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