Bobo is tired of all kinds of hard LIS (Longest Increasing Subsequence) problems,
so he decides to make himself some easier one.
Bobo wants to build a sequence of integers

,
where

lies in the range

(that is,

).
Let
)
be the length of longest increasing subsequence of

.
It's clear that
%20%5Cleq%20n)
.
Bobo would like to find

which is the number of sequences whose
%20%3D%20k)
for

.
Note that a sequence

is a increasing sequence of

only if: