/* C++ program to calculate A258218 Author: M. Wang Email Address: atvv@foxmail.com Compiler: MinGW compiler Compiler Version: v4.9.2 (tdm64-1) OEIS URL: https://oeis.org/A258218 */ #include #include #include #include using namespace std; template int bitcnt(T t){ int ret; ret=0; while(t!=0){ ret++; t^=t&-t; } return ret; } void insert_ans(set< __int64 > & ansset,__int64 i,int n){ int cx; __int64 s=i; int n2=n-2; for(;;){ s=s>>1|(s&1)<ansset; int n1=n-1; __int64 i; int n2=n-2; __int64 cx; i=0; cx=1; cx<<=n1; for(;cx--;i++){ if(bitcnt(i)==n/2){ int cx; __int64 s=i; do{ s=s>>1|(s&1)<