y [ ] [ ] is used for difference table and y [ ] [ 0 ] used for input
double [ , ] y = new double [ n , n ] ; y [ 0 , 0 ] = 46 ; y [ 1 , 0 ] = 66 ; y [ 2 , 0 ] = 81 ; y [ 3 , 0 ] = 93 ; y [ 4 , 0 ] = 101 ;