Problem K. sacul
时间限制 1000 ms
内存限制 32 MB
Patrick Star found a kind of magical matrixs, he named them $HMBB$ !!!
We use $p$ to express the $c$-th prime number.
The size of $HMBB_i$ is $p^i * p^i$ !
What is more surprising is that :
1. For any $n$, the element on the i-th row j-th column $HMBB_n[i][j]$ = $(C(i, j)\ mod\ p) > 0)$ ? $1$ : $0$.
2. Where $C(i, j)$ is count of method to choose $j$ balls (unordered) from $i$ balls which are pairwise distinct.
3. Note that rows and columns both count from zero.
Patrick Star defined $F[n][k]$ the sum of all elements of $(HMBB_n)^k$, $F[n][k] = \sum_{i = 0}^{p^n-1}\sum_{j=0}^{p^n-1}HMBB_n^k[i][j]$
Now Patrick wants to know $(\sum_{i=1}^n\sum_{j=1}^kF[i][j])\ mod\ (10^9 + 7)$ !
输入数据
输出数据
For each test case output one line denotes the answer that Patrick Star wants to know.
样例输入
样例输出
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