Euro coins Euro coins There are eight euro coin denominations, ranging from one cent to two euros (the euro is divided into a hundred cents). The coins first came into use in 2002. They have a common reverse, portraying a map of Europe, but each country in the eurozone has its own design on the obverse, which means that each coin has a variety of different designs in circulation at once. Four European microstates which use the euro as their currency also have the right to mint coins with their own designs on the obverse side. The coins, and various commemorative coins,
Coin problem Coin problem The coin problem (also referred to as the Frobenius coin problem or Frobenius problem, after the mathematician Ferdinand Frobenius) is a mathematical problem that asks for the largest monetary amount that cannot be obtained using only coins of specified denominations. For example, the largest amount that cannot be obtained using only coins of 3 and 5 units is 7 units. The solution to this problem for a given set of coin denominations is called the Frobenius number of the set. The Frobenius number exists as long as the set of coin denominations has no common divisor greater than