<s>
In	O
mathematics	O
,	O
the	O
Skolem	B-Algorithm
problem	I-Algorithm
is	O
the	O
problem	O
of	O
determining	O
whether	O
the	O
values	O
of	O
a	O
constant-recursive	O
sequence	O
include	O
the	O
number	O
zero	O
.	O
</s>
<s>
The	O
Skolem	B-Algorithm
problem	I-Algorithm
is	O
named	O
after	O
Thoralf	O
Skolem	O
,	O
because	O
of	O
his	O
1933	O
paper	O
proving	O
the	O
Skolem	O
–	O
Mahler	O
–	O
Lech	O
theorem	O
on	O
the	O
zeros	O
of	O
a	O
sequence	O
satisfying	O
a	O
linear	O
recurrence	O
with	O
constant	O
coefficients	O
.	O
</s>
<s>
The	O
remaining	O
difficult	O
part	O
of	O
the	O
Skolem	B-Algorithm
problem	I-Algorithm
is	O
determining	O
whether	O
the	O
finite	O
set	O
of	O
non-repeating	O
zeros	O
is	O
empty	O
or	O
not	O
.	O
</s>
<s>
Partial	O
solutions	O
to	O
the	O
Skolem	B-Algorithm
problem	I-Algorithm
are	O
known	O
,	O
covering	O
the	O
special	O
case	O
of	O
the	O
problem	O
for	O
recurrences	O
of	O
degree	O
at	O
most	O
four	O
.	O
</s>
<s>
For	O
integer	O
recurrences	O
,	O
the	O
Skolem	B-Algorithm
problem	I-Algorithm
is	O
known	O
to	O
be	O
NP-hard	O
.	O
</s>
