MCNPX Visual Editor Version X_24J 
c     Created on: Saturday, August 15, 2015 at 09:40                            
    1     0         -1  imp:n=1  
    2     0         3 -2  imp:n=1  
    3     0         2  imp:n=0  

    1        so 50 
    2        so 100 
    3        gq 1 1 1 0 0 0 0 0 0 -2500 

mode  n
sdef                                                                            
nps  10000