5608：function

题目描述

There is a function $f(x)$,which is defined on the natural numbers set $N$,satisfies the following eqaution

$N^2-3N+2=\sum_{d|N} f(d)$

calulate $\sum_{i=1}^{N} f(i)$ $~mod~10^9+7$.

输入解释

the first line contains a positive integer T,means the number of the test cases.

next T lines there is a number N

$T \leq 500, N \leq 10^9$

only $5~$test cases has $N > 10^6$.

输出解释

$T$lines,each line contains a number,means the answer to the $i$-th test case.

输入样例

1
3

输出样例

2

$1^2-3*1+2=f(1)=0$
$2^2-3*2+2=f(2)+f(1)=0->f(2)=0$
$3^2-3*3+2=f(3)+f(1)=2->f(3)=2$
$f(1)+f(2)+f(3)=2$

来自杭电HDUOJ的附加信息

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hujie

该题目是Virtual Judge题目，来自杭电HDUOJ

题目来源 BestCoder Round #68 (div.2)

源链接： HDU-5608

最后修改于 2020-10-25T23:24:09+00:00 由爬虫自动更新

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通过率 --%

时间上限	内存上限
6000/3000MS(Java/Others)	65536/65536K(Java/Others)