It looks as if jimv got there before me, in fact. (I hadn’t seen his comment when I wrote mine. Sometimes some time elapses between when I open a page and when I actually read its contents, and sometimes I forget that I ought to refresh before commenting...)
I don’t think this is correct. I think that the closest is Goldbach’s conjecture, which is for even numbers and is unproven.
I think 27 is the first counter example. 27-2 is 25, which is not a prime. 27-(any prime other than 2) is even, so not a prime.
I think of primes as analogous to elements because of factorisation, not summation.
A bit later in the essay, just before the introduction of twin primes, 9 is included in the list of primes.
Thanks, gjm pointed that out too! I’ll credit you as well.
It looks as if jimv got there before me, in fact. (I hadn’t seen his comment when I wrote mine. Sometimes some time elapses between when I open a page and when I actually read its contents, and sometimes I forget that I ought to refresh before commenting...)
No problem!
There’s still this slip (the erroneous 9) in the text:
Thank you so much for proofreading!