A Jordan algebra which is not isomorphic to a subalgebra.
Exceptional Jordan Algebra
See also
Jordan Algebra, Special Jordan AlgebraExplore with Wolfram|Alpha
References
Albert, A. A. "A Construction of Exceptional Jordan Division Algebras." Ann. Math. 67, 1-28, 1958.Albert, A. A. and Jacobson, N. "On Reduced Exceptional Simple Jordan Algebra." Ann. Math. 66, 400-417, 1957.Referenced on Wolfram|Alpha
Exceptional Jordan AlgebraCite this as:
Weisstein, Eric W. "Exceptional Jordan Algebra." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/ExceptionalJordanAlgebra.html