• CompassRed@discuss.tchncs.de
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    1 year ago

    2 may be the only even prime - that is it’s the only prime divisible by 2 - but 3 is the only prime divisible by 3 and 5 is the only prime divisible by 5, so I fail to see how this is unique.

  • EatBorekYouWreck@lemmy.world
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    1 year ago

    Even vs odd numbers are not as important as we think they are. We could do the same to any other prime number. 2 is the only even prime (meaning it is divisible by 2) 3 is the only number divisible by 3. 5 is the only prime divisible by 5. When you think about the definition of prime numbers, this is a trivial conclusion.

    Tldr: be mindful of your conventions.

    • alvvayson@lemmy.world
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      1 year ago

      Yes, but not really.

      With 2, the natural numbers divide into equal halves. One of which we call odd and the other even. And we use this property a lot in math.

      If you do it with 3, then one group is going to be a third and the other two thirds (ignore that both sets are infinite, you may assume a continuous finite subset of the natural numbers for this argument).

      And this imbalance only gets worse with bigger primes.

      So yes, 2 is special. It is the first and smallest prime and it is the number that primarily underlies concepts such as balance, symmetry, duplication and equality.

      • EatBorekYouWreck@lemmy.world
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        1 year ago

        But why would you divide the numbers to two sets? It is reasonable for when considering 2, but if you really want to generalize, for 3 you’d need to divide the numbers to three sets. One that divide by 3, one that has remainder of 1 and one that has remainder of 2. This way you have 3 symmetric sets of numbers and you can give them special names and find their special properties and assign importance to them. This can also be done for 5 with 5 symmetric sets, 7, 11, and any other prime number.

  • AssortedBiscuits [they/them]@hexbear.net
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    1 year ago

    The meme works better if it’s 1 instead of 2. 1 is mostly not considered a prime number because a bunch of theorems like the fundamental theorem of arithmetic would have to be reworked to say “prime numbers greater than 1.” However, just because 1 is not a prime number doesn’t mean it’s a composite number, so 1 is a number that is neither prime nor composite.

    • wischi@programming.dev
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      1 year ago

      And how is “even” special? Two is the only prime that’s divisible by two but three is also the only prime divisible by three.

      • Whirlybird@aussie.zone
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        1 year ago

        Well 2 is the outlier because it’s the only even prime. It might not be “special” but it is unique out of all of the prime numbers.

        • wischi@programming.dev
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          1 year ago

          “even” just means divisible by two. So it’s not unique at all. Two is the only prime that’s even divisible by two and three is the only prime that’s divisible by three. You just think two is a special prime because there is a word for “divisible by two” but the prime two isn’t any more special or unique in any meaningful way than any other prime.

          • Whirlybird@aussie.zone
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            1 year ago

            It’s unique because all the others are odd numbers. This is crazy that you’re trying to argue this.

            • wischi@programming.dev
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              1 year ago

              Of couse all the others are odd because otherwise they wouldn’t be prime. All primes after three are also not divisible by three… “magic”. The only difference is that there are is no word like “even” or “odd” for “divisible by three” or “not divisible by three”.

              • Whirlybird@aussie.zone
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                1 year ago

                only difference is that there are is no word like “even” or “odd” for “divisible by three” or “not divisible by three”.

                Yep, hence why 2 is unique - there is a word to describe numbers that are divisible by 2, and 2 is the only one of those that is a prime number.

                It seems that you don’t know what the word “unique” means.