IIRC, the computer went through thousands of permutations of maps and demonstrated the proof.
At the time there was some controversy as to whether or not having a computer do all the grunt work counted, LOL. Like you could hire someone to compost their brain doing it manually.
Wiki 'four color map problem'.
At the time there was some controversy as to whether or not having a computer do all the grunt work counted, LOL. Like you could hire someone to compost their brain doing it manually.
Wiki 'four color map problem'.