[r-t] Exhausted search spaces

Ian Broster ian at broster.co.uk
Thu Feb 4 22:36:35 UTC 2010

> I find this rate of progress astonishing.  I've coded up what I reckon  
> is a pretty smart search algorithm, while not being too specific to  
> PB6.  But my code only found 602,675 methods in 6 minutes.

Intrigued, I also coded up a few lines of code tonight to look for extents  
of PB6.

It's been running 75 minutes on a cheap laptop and found 36 * 10^6 extents  
so far, excluding all rotations.
So, on average that's 480,000 per minute, which you might just map to 2.8  
million in 6 minutes.

As you say, it's hard to estimate the progress because of the tree pruning.

There is nothing notable in my implementation, it's merely searching for  
trees. It's single threaded, written in C, with little thought on  


Ian Broster

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