When Bruce learned set theory, he assigned a homework question to his students.
Given a positive integer , find the number of subsets of the whole set
that satisfies the following constraint: if an integer
is in the subset, then the integers
and
are not in the subset. For example, given
, the whole set is
. The number of subsets satisfying the constraint is
, including the empty set:
,
,
,
,
,
,
, and
.
Input Specification
The input will consist of one integer
.
Output Specification
Output the number of subsets that satisfy the above constraints mod
.
Sample Input
4
Sample Output
8
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