points := [];
points := [op(points), [15, 44]];
points := [op(points), [20, 62]];
points := [op(points), [30, 115]];
points := [op(points), [50, 224]];


for i from 1 to 4 do
   x[i] := points[i,1]; y[i] := points[i,2];
od;

x_coords := []; y_coords:=[];
for i from 1 to 4 do
    x_coords := [op(x_coords), x[i]];
    y_coords := [op(y_coords), y[i]];
od;

model := stats[fit,leastsquare[[x,y],y=a*x*ln(x) + b*x + c, {a,b,c}]]([x_coords, y_coords]);