Product after Sol LeWitt

Inspired by the drawing Successive Rows of Horizontal, Straight Lines from Top to Bottom, and Vertical, Straight Lines from Left to Right, 1972 by Sol LeWitt, first seen by me at vjeranski's art tumblr, http://vjeranski.tumblr.com/post/112892688148/sol-lewitt-successive-rows-of-horizontal-straight Lovely sketch, with a construction that has similar sights in math. Tim Cieplowski pointed out this colorful proportional multiplication table. http://thegriddle.net/handouts/mult_color_num.pdf In this sketch you can set the factors and have them show or not show.