• magic_lobster_party@fedia.io
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    5 days ago

    If there’s a number that’s the most oddball in the multiplication table, it’s 7.

    It’s a prime number that doesn’t share any common divisors with 10, and isn’t adjacent to a divisor of 10 either.

    2 and 5 are common divisors of 10, so they’re piece of cake.

    3 is so small and close to 2, so it’s not too difficult to get.

    9 is one off from 10, so it has a very predictable pattern.

    4, 6 and 8 are even numbers, so they share common divisors with 10.

    • sugar_in_your_tea@sh.itjust.works
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      5 days ago

      3 is easy because of the “digits sum to 3” trick, if you get stuck counting by 3s, it’s easy to reset. Oh, and the proof for this is based on our 10-based number system, so your point absolutely stands.