Ed Pegg

In 1356, Narayana posed a question in his book Gaṇita Kaumudi: "A cow gives birth to a calf every year. In turn, the calf gives birth to another calf when it is three years old. What is the number of progeny produced during twenty years by one cow?" This is now known as Narayana's cows sequence. The Narayana's cows sequence constant, cow=1.4655712318767680266567312252199391080255775684723, is the limit ratio between neighboring terms.

November saw the twentieth anniversary of ‘The Innovator’s Dilemma’, the book in which Clayton Christensen sets out the theory of disruptive innovation. However, in an article in the Harvard Business Review, Christensen commented that he believed his theory to be ‘possibly the most misunderstood theory in the world’. So how is it misunderstood? In the popular conscience, ‘disruption’ seems to apply primarily to new innovations that create new products and new business processes.

October 18, 2005--After a nearly 15-year wait, the complete 4-volume set of Michael Trott's definitive Mathematica GuideBooks is now available. This news story presents a small sampling of the stunning images, visualizations, and mathematical computations contained in these books, together with a short description of how they came to be.