Not a Penny More, Not a Penny Less the book was developed and published by Domark, and released in 1987 for the Amstrad CPC, Atari XL, BBC Micro, Commodore 64 and ZX Spectrum computers. Not a Penny More, Not a Penny Less Not a Penny More, Not a Penny Less was Jeffrey Archer's first novel, first published in 1976. It was said to have been inspired by Archer's real-life experience of near-bankruptcy. Harvey Metcalfe, over 40 years, has mastered the shady deal in advancing from messenger boy to mogul. But by selling inflated oil stock, he has cheated the wrong men - Stephen Bradley, an American professor at
Penny graph are less than three units from the convex hull of the pennies have fewer neighbors. Based on a more precise version of this argument, one can show that every penny graph with vertices has at most edges. Some penny graphs, formed by arranging the pennies in a triangular grid, have exactly this number of edges. By arranging the pennies in a square grid, or in the form of certain squaregraphs, one can form triangle-free penny graphs whose number of edges is at least Swanepoel suggested that this bound is tight. Proving this, or finding a better bound, remains open. It