John-Sachs Determinantal Method

This scheme rather readily lends itself to hand computation on polyhex benzenoids of up to a dozen or so hexagonal rings, and of course even larger systems when computer automated The scheme is based on a 1-to-l 

The consideration of the sets of mutually self-avoiding walkers has a wider import in revealing a fundamental invariant (the number of walkers) which turns out to be important in transfer-matrix solutions, as applied to polymer graphs extending even to the 2-dimensional limit [141,142]. Also this invariant or order has physical implications [71,72,84,85,152]. 

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