linear= \colorblue a + \colorred b                                                                                                                   
square= \colorblue a  · \colorblue a + \colorblue a  · \colorred b + \colorred b  · \colorred b                                                      
 cubic= \colorblue a  · \colorblue a  · \colorblue a + \colorblue a  · \colorblue a  · \colorred b + \colorblue a  · \colorred b  · \colorred b + \co
                                                                                             
                                                                                             
                                                       lorred b  · \colorred b  · \colorred b