sim_difeq.java solving 4 equations
simple numeric check, answer 1, 2, 3, 4
X=0.1 Y[0]=0.09999999999999998 Y[1]=0.19999999999999996
                    Y[2]=0.3 Y[3]=0.3999999999999999
X=0.2 Y[0]=0.19999999999999996 Y[1]=0.3999999999999999
                    Y[2]=0.6000000000000001 Y[3]=0.7999999999999998
X=0.3 Y[0]=0.29999999999999993 Y[1]=0.5999999999999999
                    Y[2]=0.9000000000000001 Y[3]=1.1999999999999997
X=0.39999999999999997 Y[0]=0.3999999999999999 Y[1]=0.7999999999999998
                    Y[2]=1.2000000000000002 Y[3]=1.5999999999999996
X=0.49999999999999994 Y[0]=0.49999999999999994 Y[1]=0.9999999999999999
                    Y[2]=1.5 Y[3]=1.9999999999999998
X=0.6 Y[0]=0.5999999999999999 Y[1]=1.1999999999999997
                    Y[2]=1.7999999999999998 Y[3]=2.3999999999999995
X=0.7000000000000001 Y[0]=0.7 Y[1]=1.4
                    Y[2]=2.0999999999999996 Y[3]=2.8
X=0.8000000000000002 Y[0]=0.8 Y[1]=1.6
                    Y[2]=2.3999999999999995 Y[3]=3.2
X=0.9000000000000002 Y[0]=0.9000000000000001 Y[1]=1.8000000000000003
                    Y[2]=2.6999999999999993 Y[3]=3.6000000000000005
X=1.0000000000000002 Y[0]=1.0000000000000002 Y[1]=2.0000000000000004
                    Y[2]=2.999999999999999 Y[3]=4.000000000000001
 
fourth order check 1, 1/2, 1/6, 1/24
X=1.0000000000000007 Y[0]=1.0000000000000007  Y[1]=0.500000000000001
                    Y[2]=0.1666666666666669 Y[3]=0.04166666666666671
Y[3]*24.0 =1.000000000000001
 
sim_difeq.java finished