题意
给定(p,k),(T)次查询,每次询问给定(n),求(sumlimits_{i=1}^n i^k(\%~p))。((2le n,m,kle 10^{18},1le Tle 3*10^3),(p)最大质因子不超过(3*10^5))
做法
(p)最大质因子不超过(3*10^5),直接暴力分解一下(p=prod p_i^{a_i})
单独考虑一个(p_i^{a_i}),这个(i)跟下面那个不同啊,由于容易区分就不管重名了
[egin{aligned}\
sumlimits_{i=1}^n j^k&=sumlimits_{i=1}^n (ap_i+b)^k\
&=sumlimits_{i=1}^n sumlimits_{j=0}^{min(k,a_i)}{kchoose j}(ap_i)^j b^{k-j}\
&=sumlimits_{j=0}^{min(k,a_i)}{kchoose j}p^j sumlimits_{i=1}^n a^j b^{k-j}\
&=sumlimits_{j=0}^{min(k,a_i)}{kchoose j}p^j (sumlimits_{a=0}^{frac{n}{p_i}-1} a^jsumlimits_{b=0}^{p_i-1}b^{k-j}+(frac{n}{p_i})^{j}sumlimits_{b=0}^{n\%p_i} b^{k-j})\
end{aligned}]