This cache is not at the publised co-ordinates.
We often find it hard to assess how difficult a puzzle will be, This time we fell into the trap of thinking it would be easier that it is. So we have made a couple of changes which we hope will give some extra hints.
There were originally seven, then six, and now, at the time this puzzle was set, seven again (although that number has changed again subsequently). The one that was excluded for a while is also something of an "odd man out" compared to the other six.
From the images below you need to find numbers for letters A to F. Then identify the "odd man out" which becomes G.
The cache can be found at:
N51 (B-A).(D+E-1)*G W000 (B+C-A+F).((D+F)*(B+C)+G-F)
A little bit of agility is needed to get to this cache, hence the terrain rating. Please cache within your abilities.