how to run mathematical operations in simulink models in the model contain feed back

hi i am doing simulink blocks for these operations

e(n) = d(n) – y(n);

g(n) =P(n-1) x*(n){ L +x T (n)P(n-1)x*(n)}-1 ;

P(n) = P(n-1)-g(n) x T (n) P(n-1) ;

w(n)=w(n-1)+e(n).g(n);

 y(n)=xT(n)w(n-1).

In these operation contain the feed back, so signal is passed through the blocks error is occred. the feed back is not gives sufficient values it gives only ones,