<s>
In	O
operator	O
theory	O
,	O
a	O
set	O
is	O
said	O
to	O
be	O
a	O
spectral	B-Algorithm
set	I-Algorithm
for	O
a	O
(	O
possibly	O
unbounded	O
)	O
linear	O
operator	O
on	O
a	O
Banach	O
space	O
if	O
the	O
spectrum	O
of	O
is	O
in	O
and	O
von-Neumann	O
'	O
s	O
inequality	O
holds	O
for	O
on	O
-	O
i.e.	O
</s>
<s>
For	O
a	O
detailed	O
discussion	O
of	O
spectral	B-Algorithm
sets	I-Algorithm
and	O
von	O
Neumann	O
's	O
inequality	O
,	O
see	O
.	O
</s>
