include

include

using namespace std;

int main()
{
int i;
float s,n,x,fakt,stepen;
cin>>n>>x;
s=0;
stepen=1;
fakt=1;
for(i=1;i<=n;i++)
{
fakt=fakt*i;

stepen=stepen*x;
s=s+(stepen/fakt);
}
cout<< s;

return 0;

}