ctrss的博客

Visible Lattice PointsTime Limit: 1000MS Memory Limit: 65536KTotal Submissions: 6329 Accepted: 3774DescriptionA lattice point (x, y) in the first quadrant (x an

Farey SequenceTime Limit: 1000MS Memory Limit: 65536KTotal Submissions: 14434 Accepted: 5719DescriptionThe Farey Sequence Fn for any integer n with n >= 2 is the

Happy 2006Time Limit: 3000MS Memory Limit: 65536KTotal Submissions: 10751 Accepted: 3744DescriptionTwo positive integers are said to be relatively prime to each o

Primitive RootsTime Limit: 1000MS Memory Limit: 10000KTotal Submissions: 3601 Accepted: 2101DescriptionWe say that integer x, 0 i mod p) | 1 <= i <= p-1 } is eq

第一次接触欧拉函数，phi(x)为小于等于x且与x互质的数的个数……先介绍一些基本定理1.定义在所有正整数上的函数成为算数函数。2.一个算术函数f，如果对于两个互素整数m,n有f(nm)=f(n)*f(m)则称f为积性函数。如果对于任意两个正整数mn有f(nm)=f(n)*f(m)则称f为完全积性函数。3.如果f是一个积性函数，则对于正整数n=p1^a1*p2^a2……（pi为素数），