Looking back at my quantum mechanics notes, the angular momentum addition theorem is listed as:
$j=j_1+j_2,j_1+j_2-1, ..., |j_1-j_2| $ (Using conventional notation)
, but I'm a little unsure how to interpret the introduction of the modulus operation ($|...|$) and couldn't easily find any examples.
I'm assuming you apply the modulus to any expression which would otherwise yield a negative value for $j$?
I'd appreciate a nod from someone in the know :-).