| Answer :
Just six
different rings may be formed without breaking the
conditions.
Here is one way of effecting the arrangements.
| A |
B |
C |
D |
E |
F |
G |
H |
I |
J |
K |
L |
M |
| A |
C |
E |
G |
I |
K |
M |
B |
D |
F |
H |
J |
L |
| A |
D |
G |
J |
M |
C |
F |
I |
L |
B |
E |
H |
K |
| A |
E |
I |
M |
D |
H |
L |
C |
G |
K |
B |
F |
J |
| A |
F |
K |
C |
H |
M |
E |
J |
B |
G |
L |
D |
I |
| A |
G |
M |
F |
L |
E |
K |
D |
J |
C |
I |
B |
H |
Join the ends and you have the six rings.
Lucas devised a simple mechanical method for
obtaining the n
rings that
may be formed under the conditions by 2n+1 children.
|