3 connectors so that joined numbers are not 'next door' numbers (i.e. 2 is not joined to 1 or 3)
is this the only way that you can do this?
join the numbers 1 to 5 with 6 connectors so that connected numbers are not 'next door' numbers
any other ways?
prove that there are essentially two different solutions for an arrangement around a hexagon
why triangular numbers for the numbers of connectors?