• 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.

        • Foofighter
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          1 year ago

          Not sure about how relevant this in reality, but when it comes to alternating series, this might be relevant. For example the Fourier series expansion of cosine and other trig function?

          • EatBorekYouWreck@lemmy.world
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            1 year ago

            But then it is more natural to use the complex version of the Fourier series, which has a neat symmetric notation

            • Foofighter
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              1 year ago

              True, but normally, you’d introduce trig functions before complex numbers. Anyhow: I appreciate the meme and the complete over the top discussion about it :D

        • alvvayson@lemmy.world
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          1 year ago

          Then you have one set that contains multiples of 3 and two sets that do not, so it is not symmetric.

          • rbhfd@lemmy.world
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            1 year ago

            You’d have one set that are multiples of 3, one set that are multiples of 3 plus 1, and one stat that are multiples of 3 minus 1 (or plus 2)

            • alvvayson@lemmy.world
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              1 year ago

              How do you people even math.

              You might as well use a composite number if you want to create useless sets of numbers.