For an algebra , the associator is the trilinear map given by
The associator is identically zero iff is associative.
For an algebra , the associator is the trilinear map given by
The associator is identically zero iff is associative.
Weisstein, Eric W. "Associator." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/Associator.html