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求114514^n的因子和mod 19260817

求 114514n114514^n114514n 的因子和 mod19260817mod 19260817mod19260817 , 192608171926081719260817 是质数, 114514114514114514 的质因子是 2,31,18472,31,18472,31,1847 。

2,12 ,12,1 31,131 ,131,1 1847,11847 ,11847,1 114514114514114514 的因子和为 s(2)∗s(31)∗s(1847)=3∗32∗1845=177120‬s(2)*s(31)*s(1847)=3*32*1845=177120‬s(2)∗s(31)∗s(1847)=3∗32∗1845=177120‬ 如果 ppp 是素数 s(pn)=1+p+p2+...+pn=(p(n+1)−1)/(p−1)s(p^n)=1+p+p^2+...+p^n= (p^(n+1)-1) /(p-1)s(pn)=1+p+p2+...+pn=(p(n+1)−1)/(p−1) s(114514n)=s(2n)∗s(31n)∗s(1847n)s(114514^n)=s(2^n)*s(31^n)*s(1847^n)s(114514n)=s(2n)∗s(31n)∗s(1847n) a=s(2n)=2(n+1)−1a=s(2^n)=2^(n+1)-1a=s(2n)=2(n+1)−1 b=s(31n)=(31(n+1)−1)/30b=s(31^n)=(31^(n+1)-1)/30b=s(31n)=(31(n+1)−1)/30 c=s(1847n)=(1847(n+1)−1)/1846c=s(1847^n)=(1847^(n+1)-1)/1846c=s(1847n)=(1847(n+1)−1)/1846 303030 的逆元 109144631091446310914463 184618461846 的逆元 138769713876971387697 a=(pow(2,n+1,19260817)−1)%19260817a=(pow(2,n+1,19260817)-1)\%19260817a=(pow(2,n+1,19260817)−1)%19260817 b=(pow(31,n+1,19260817)−1)∗10914463)%19260817b=(pow(31,n+1,19260817)-1)*10914463)\%19260817b=(pow(31,n+1,19260817)−1)∗10914463)%19260817 c=(pow(1847,n+1,19260817)−1)∗1387697)%19260817c=(pow(1847,n+1,19260817)-1)*1387697)\%19260817c=(pow(1847,n+1,19260817)−1)∗1387697)%19260817 ans=(a∗b∗c)%19260817;ans=(a*b*c)\%19260817;ans=(a∗b∗c)%19260817; AC代码:

ll qpow(ll x, ll n, ll mod)

{ ll res = 1; while (n) { if (n & 1) res = (res * x) % mod; x = x * x % mod, n >>= 1; } return res; }

const int mod = 19260817; int main() { int t; int n; sd(n); ll a = (qpow(2, n + 1, mod) - 1) % mod; ll inv1 = qpow(30, mod - 2, mod); ll b = (((qpow(31, n + 1, mod) - 1) * inv1) % mod); ll inv2 = qpow(1846, mod - 2, mod); ll c = (((qpow(1847, n + 1, mod) - 1) * inv2) % mod); ll ans = (a * b % mod * c % mod) % mod; pld(ans); return 0; }

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