function zad1r(n,i,c0)
if(i<=n)
   if(mod(i,2)==0)
      disp(i);
      c1=0.5*c0
      i=i+1;
      zad1r(n,i,c1);
    else
      disp(i);
      c1=3*c0+1
      i=i+1;
      zad1r(n,i,c1);
   endif
endif
endfunction