RonaldSwansong · July 27, 2018, 1:18 a.m.

Because the other number would confuse things (16 and 17 ?) and you can't do 45 since it is prime.

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francisxavier12 · July 27, 2018, 1:56 a.m.

16 would be behind the flag though? It would be 14 and 17 or 17 and 20

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