An exhibit of "Matematica viva", in Lisbon (Portugal) that shows that we need six colours ...
This blanket represents a map of 24 paired regions; a couple of regions is identified by t...
The figure shows a map on a Moebius strip which consists of six regions, each of them is a...
The animation shows how to colour a map on the Moebius strip; the map consists of six regi...
This map represents a map of 24 paired regions; a couple of regions is identified by the s...
