👉 A tetrad is a type of number system in which each digit in a number can have two values, with one value being positive and the other negative. For example, the number 12345 has three different tetrads: - 1: +1, -1, +1, -1 - 2: +2, -2, +2, -2 - 3: +3, -3, +3, -3 -
