This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A212951 #16 Mar 09 2018 03:21:45 %S A212951 1,2,5,10,20,50,100,133,200 %N A212951 Amounts (in hundredths of a Euro) of coins in denominations suggested by Shallit. %C A212951 The European Union uses eight coins - worth 1, 2, 5, 10, 20, and 50 cents, plus 1- and 2-Euro coins - with a range of values from 0 to 499. The average cost of making change in Europe, _Jeffrey Shallit_ calculates, is 4.6 coins. The best way to lower the cost, to 3.92, would be for Europeans to add yet another coin, worth either 1.33 or 1.37 Euros (the sequence as shown uses 133, though 137 is an equally valid solution). %H A212951 Alan Burdick, <a href="http://discovermagazine.com/2003/oct/featscienceof">The Physics of ... Pocket Change. What we really need to solve the problem of loose and useless lucre is a new coin</a>, Discover, October 2003 issue; published online October 1, 2003. %e A212951 1, 2, 5, 10, 20, and 50 cents, plus 1- and 2-Euro coins (100 and 200 cents), and the proposed 1.33-Euro coin (133 cents). %Y A212951 Cf. A212773, A212774, A008588, A008593, A008597, A008598, A135631. %Y A212951 Cf. A208953 (analog for American coins). %Y A212951 Cf. A212950 (analog for Canadian coins). %K A212951 nonn,fini,full %O A212951 1,2 %A A212951 _Jonathan Vos Post_, May 31 2012