The Crystal Palace pane of glass (49 inches) as the hypotenuse of a right-angled triangle, thereby creating a triangle with a length-to-height ratio of 2.5:1, whose base (adjacent side) was 4 feet long. By mirroring this triangle he obtained the 8-foot-wide gables that formed the vertical faces at either end of the prism, each of which was 24' long. With this arrangement, Paxton could glaze the entire roof surface with identical panes that did not need to be trimmed. Paxton placed three of these 8' x 24' roof units side-by-side, horizontally supported by a grid of cast iron beams, which was held up
Floyd's triangle of an "n" × "n" magic square . Summing up the row sums in Floyd's triangle reveals the doubly triangular numbers (triangular numbers with an index that is triangular) 1 = 1 = T(T(1)) <br><br><br> 1 = 6 = T(T(2)) <br> 2 + 3 <br><br><br> 1 <br> 2 + 3 = 21 = T(T(3))<br> 4 + 5 + 6 <br> Floyd's triangle Floyd's triangle is a right-angled triangular array of natural numbers, used in computer science education. It is named after Robert Floyd. It is defined by filling the rows of the triangle with consecutive numbers, starting with a 1