We conjecture: if integers x_1,...,x_n satisfy (x_1)^2>2^(2^n) \vee ...\vee
(x_n)^2>2^(2^n), then (\forall i \in {1,...,n} (x_i=1 \Rightarrow y_i=1))
\wedge (\forall i,j,k \in {1,...,n} (x_i+x_j=x_k \Rightarrow y_i+y_j=y_k))
\wedge (\forall i,j,k \in {1,...,n} (x_i \cdot x_j=x_k \Rightarrow y_i \cdot
y_j=y_k)) for some integers y_1,...,y_n satisfying (y_1)^2+...+(y_n)^2>n \cdot
2^(2^n)+(x_1)^2+...+(x_n)^2.
Let E_n={x_i=1, x_i+x_j=x_k, x_i \cdot x_j=x_k: i,j,k \in {1,...,n}}, K \in
{Z,Q,R,C}. We conjecture that if a system S \subseteq E_n has only finitely
many solutions in K, then their number does not exceed 2^n. We prove this bound
for K=C. We construct a system S \subseteq E_{21} such that S has infinitely
many integer solutions and S has no integer solution in
[-2^{2^{21-1}},2^{2^{21-1}}]^{21}. We conjecture that if a system S \subseteq
E_n has a finite number of solutions in K, then each such solution
(x_1,...,x_n) satisfies (|x_1|,...,|x_n|) \in [0,2^{2^{n-1}}]^n.