Fnargs are either red or blue and have 2, 3 or 4 heads. A group of six Fnargs consisting of one of each possible form is made to line up such that no immediate neighbours are the same colour nor have the same number of heads. How many ways are there of lining them up from left to right?
Select one option, then click Submit.
12
24
60
120
720
Select an option, then submit.
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Senior Mathematical Challenge 2015 (2015)
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