# Combinatorics, Algorithm, and Humanity

a lovely story on combinatorics problem, algorithm, and humanity.

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- 1568758030464750013214100
- 182413291514248049241470885236
- 64528039343270018963357185158482118
- 69450664761521361664274701548907358996488

the sequence is “Number of nonintersecting (or self-avoiding) rook paths joining opposite corners of an n X n grid.” , sequence id A007764, see https://oeis.org/A007764

there isn't a closed form formula know so far. We have counted up to f[26].

This problem, seems to be spurred by a computer game named The Witness.

If you have a question, put $5 at patreon and message me.