[math-fun] Geometry of Number Walls Update

A brief intro & summary of recent number wall activity has been uploaded at https://www.dropbox.com/s/rocryne1zhp98of/geom_wall_update.txt , avoiding the dreaded Gmail spurious line breaks (why?, why?), and permitting covert correction of my inevitable catastrophic typos. But Dropbox descends steadily into inutility, a recent `improvement' being automatic updates which cannot be disabled: the resulting potential for chaos could surely have been foreseen! Can anyone suggest acceptable alternatives? Fred Lunnon