On the number of spurious memories in the Hopfield model (neural network)
Jehoshua Bruck, Vwani Roychowdhury · IEEE Transactions on Information Theory · 1990
The outer-product method for programming the Hopfield model is discussed. The method can result in many spurious stable states-exponential in the number of vectors that are to be stored-even in the case when the vectors are orthogonal.>