#include<stdio.h>
#include<math.h>
#include<stdlib.h>
#define PI 3.1415926
int n;
double x,dx,sum, factor, chi, factor2;
main(int argc, char*argv[]){
chi=(double)atof(argv[1]);

factor=2.0*PI*PI*PI*PI*PI/(24.0);
factor2=sqrt((2.0*PI)*(2.0*PI)*(2.0*PI)*(2.0*PI)*(2.0*PI));
dx=chi/1000.0;
sum=0.0;
for(n=0;n<1000;n++){
x=(double)n*dx;
sum=sum+exp(-x*x/2.0)*pow(x,9.0)*dx;
}
sum=sum*factor/factor2;
printf("%f\n", sum);
}