y is used for difference table with y [ 0 ] used for input
var y = Array ( n ) . fill ( 0.0 ) . map ( x => Array ( n ) . fill ( 0.0 ) ) ; ; y [ 0 ] [ 0 ] = 4.000 ; y [ 1 ] [ 0 ] = 3.846 ; y [ 2 ] [ 0 ] = 3.704 ; y [ 3 ] [ 0 ] = 3.571 ; y [ 4 ] [ 0 ] = 3.448 ; y [ 5 ] [ 0 ] = 3.333 ;