$A \rightarrow B C$
$C D \rightarrow E$
$B \rightarrow D$
$E \rightarrow A$
I have these Relations for R={A,B,C,D,E}
Now I have to calculate the closure $F^+$ and give the candidate keys
I came to these relations
$A \rightarrow A$
$A \rightarrow DC$
$A \rightarrow DE$
$A \rightarrow EE$
$A \rightarrow AA$
$A \rightarrow (DC)^{2^n}$
$A \rightarrow (DE)^{2^n}$
$A \rightarrow (EE)^{2^n}$
$A \rightarrow (AA)^{2^n}$
$C \rightarrow C$
$C \rightarrow A$
$C \rightarrow BC$
$C \rightarrow DC$
$C \rightarrow DE$
$C \rightarrow EE$
$C \rightarrow AA$
$C \rightarrow (DC)^{2^n}$
$C \rightarrow (DE)^{2^n}$
$C \rightarrow (EE)^{2^n}$
$C \rightarrow (AA)^{2^n}$
$D \rightarrow A$
$D \rightarrow BC$
$D \rightarrow DC$
$D \rightarrow DE$
$D \rightarrow EE$
$D \rightarrow AA$
$D \rightarrow (DC)^{2^n}$
$D \rightarrow (DE)^{2^n}$
$D \rightarrow (EE)^{2^n}$
$D \rightarrow (AA)^{2^n}$
$CD\rightarrow CD$
$CD\rightarrow A$
$CD\rightarrow BC$
$CD\rightarrow DC$
$CD\rightarrow DE$
$CD \rightarrow EE$
$CD \rightarrow AA$
$CD \rightarrow (DC)^{2^n}$
$CD \rightarrow (DE)^{2^n}$
$CD \rightarrow (EE)^{2^n}$
$CD \rightarrow (AA)^{2^n}$
$E\rightarrow E$
$E\rightarrow BC$
$E\rightarrow DC$
$E\rightarrow DE$
$E \rightarrow EE$
$E \rightarrow AA$
$E \rightarrow (DC)^{2^n}$
$E \rightarrow (DE)^{2^n}$
$E \rightarrow (EE)^{2^n}$
$E \rightarrow (AA)^{2^n}$
$B\rightarrow B$
$B\rightarrow E$
$B\rightarrow A$
$B\rightarrow BC$
$B \rightarrow DC$
$B \rightarrow DE$
$B \rightarrow EE$
$B \rightarrow AA$
$B \rightarrow (DC)^{2^n}$
$B \rightarrow (DE)^{2^n}$
$B \rightarrow (EE)^{2^n}$
$B \rightarrow (AA)^{2^n}$
AB
$AB\rightarrow AB$
$AB\rightarrow B$
$AB\rightarrow E$
$AB\rightarrow A$
$AB\rightarrow BC$
$AB \rightarrow DC$
$AB \rightarrow DE$
$AB \rightarrow EE$
$AB \rightarrow AA$
$AB \rightarrow (DC)^{2^n}$
$AB \rightarrow (DE)^{2^n}$
$AB \rightarrow (EE)^{2^n}$
$AB \rightarrow (AA)^{2^n}$
AC
$AC \rightarrow AC$
$AC \rightarrow C$
$AC \rightarrow A$
$AC \rightarrow BC$
$AC \rightarrow DC$
$AC \rightarrow DE$
$AC \rightarrow EE$
$AC \rightarrow AA$
$AC \rightarrow (DC)^{2^n}$
$AC \rightarrow (DE)^{2^n}$
$AC \rightarrow (EE)^{2^n}$
Could someone tell me if this is correct so far? I guess I have to give all these until ABCDE on the left side.
And how do I get the candidate keys then?
