Like the ATBaSH cipher the ALBaM cipher is another way of permuting the Hebrew alphabet. It's rule is as follows: As the name implies Aleph becomes Lamed, Beth becomes Mem. Basically, Each of the twenty-two letters is shifted by eleven places. Programmatically or mathematically this could be represented as: f(x) = (x + 11) % 22 (note that % represents the modulus operator)

Both ATBaSH and ALBaM are interesting in that they are unique cases within a larger system of less notable permutations. (Permutation Meditation will hopefully discuss these and others like them in much more detail.) While ATBaSH makes the end the beginning, and the beginning the end, ALBaM turns the alphabet inside out, making the middle the outside and the outside the middle.

English might similarly be permuted in this way by shifting each letter thirteen places. This is because English has twenty-six letters. (This would be f(x) = (x+13)%26)

The generalised formula for this cipher with any letter x of any alphabet of length n would be: f(x,n) = (x + (n / 2)) % n