def newton_coef(list_x, list_y):
    n = len(list_x)
    for j in range(1,n):
        for i in range(n-1, j-1, -1 ):
            list_y[i]=(list_y[i]-list_y[i-1])/(list_x[i]-list_x[i-j])
    return list_y

if __name__ == '__main__':
    x=[3,1,5,6]
    y=[1,-3,2,4]
    print(newton_coef(x,y))