Let $\langle \operatorname{Ent},+,\cdot \rangle$ be the (complex) vector space of entire functions.
For all members $n$ of $\{1,2,3,...\}$, define $||\cdot ||_n : \operatorname{Ent} \to \mathbb{R}$ by $||f||_n = \operatorname{sup}(\{|f(z)| : |z|\leq n\})$.
$\big\langle \operatorname{Ent},+,\cdot,\{||.||_n : n\in \{1,2,3,...\}\} \big\rangle$ is a Frechet space.
For all complex numbers $z_0$ and members $g$ of $\operatorname{Ent}$, the operators $L_1,...,L_5 : \operatorname{Ent} \to \operatorname{Ent}$$L_1,...,L_4 : \operatorname{Ent} \to \operatorname{Ent}$ defined by
$(i) \quad (L_1(f))(z) = g(z)\cdot f(z)$
$(ii) \quad (L_2(f))(z) = f(z+z_0)$
$(iii) \quad (L_3(f))(z) = f(0)$$(ii) \quad (L_2(f))(z) = f(g(z))$
$(iv) \quad (L_4(f))(z) = f'(z)$$(iii) \quad (L_3(f))(z) = f'(z)$
$(v) \quad (L_5(f))(z) = \displaystyle\int_0^z f$$(iv) \quad (L_4(f))(z) = \displaystyle\int_0^z f$
are all continuous and linear.
Let $S$ be the set of all functions obtainable by the above.
Let $\mathbf{L}$ be continuous operator algebra on $\operatorname{Ent}$.
Let $T$ be the closure of $S$ as a sub-algebra of $\mathbf{L}$.
Does $\:$ $T = \mathbf{L}$ $\:$ ?
If no, is $T$ dense in $\mathbf{L}$? (uniform operator topology)
If no again, is $T$ dense in $\mathbf{L}$ in some weaker topology?