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Structure zoo

So, I'm getting better at generating structures :
but, not quite there yet. Oh, and the [1.1.1] propellane is drawn oddly (with one of its carbons at 0,0) due to a mac-specific bug in the layout. Irritating, but difficult to fix.

edit: Oh, and for interests sake, here is an auto-generated tree of graphs

Even more complex looking is this! :

which is a set of structures produced by descending to depth 6 for 5-carbon graphs.
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