Today I Learned #3: There's a wiki for everything!

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TIL that for every positive integer x, there is an easy method to construct x consecutive numbers that are not prime.
I find this nice, and it uses factorials, namely:

(n+ 1)! + 2,(n+ 1)! + 3, . . . ,(n+ 1)! + (n+ 1)

An example: for n=4, you get 122, 123, 124, 125.

(there are other series, but this is easy to construct; an example of another for n=4 would be 24, 25, 26, 27)
 
TIL that for every positive integer x, there is an easy method to construct x consecutive numbers that are not prime.
I find this nice, and it uses factorials, namely:

(n+ 1)! + 2,(n+ 1)! + 3, . . . ,(n+ 1)! + (n+ 1)

An example: for n=4, you get 122, 123, 124, 125.

(there are other series, but this is easy to construct; an example of another for n=4 would be 24, 25, 26, 27)
I am sure I am missing something, but for n=1 you get 4, 5, 6, 7 which includes 2 primes?
 
I am sure I am missing something, but for n=1 you get 4, 5, 6, 7 which includes 2 primes?

Mind the "...". For n=1 you would only have (n= ) one number. And you start from the left in the progression. [you can also start from the right, it can be written as (n+1)!+n+1, (n+1)!+n, (n+1)! +n-1,...]

for n=1 you get (n+1)!+2 = 8, while for n=2 you get (n+1)!+2 = 8 and (n+1!)+3, obviously consecutive, and actually 9 :)


Note:
Assuming the result is true for any integer (I see no reason why it wouldn't be, and I read it in a published paper; they gave no bounds for this holding true), it is interesting that you can have a gap between primes be as massive as you wish (but obviously still finite, since you start with a specific number for the size of the gap). I wonder if this can be used in conjunction with position of the next prime, that is after the gaps. I read it in a paper dealing with the twin prime conjecture.

Note#2:
While the left part of the additions for each number is obviously never prime (it has to be multiplied by 2, due to the factorial), I would like to establish how the right part being added also never produces a prime. Which means I have to read about the actual development of this method - which would have been easier if the author of the paper bothered to note anything about it, but you know how professional mathematicians refer to stuff they see as trivial without caring about non-mathematician readers :D )
 
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Til that I actually can learn something new about Kafka.
Just read in an article that Gracchus was the roman term for Jackdaw. Kafka is the czech term for that.
This is a nice touch, since Kafka has written a story titled "The hunter Gracchus", and up to now I thought the name was picked up from Gaius.

(goes without saying that the character would be standing for Kafka, but I wasn't aware of the name-tie)
 
I'm afraid I'm missing the joke :blush:.
(but then I know all that stuff, so maybe I'm not seeing it; and I'm also used to e.g. very bad acronyms http://www.acgt.me/blog?tag=jabba )
Perhaps it would be more obvious if one put a space between the second and third letters, but you need to be aware of UK rather than US spelling.
 
It is.

One sect of Taborites, the Bohemian Adamites (around 1419), dissociated themselves from other Taborites and took up the practice of going naked through towns and villages. They preached that "God dwelt in the Saints of the Last Days" and considered exclusive marriage to be a sin. The historian Norman Cohn observed: "Whereas the Taborites were strictly monogamous, in this sect free love seems to have been the rule. The Adamites declared that the chaste were unworthy to enter the Messianic kingdom ... The sect was much given to ritual naked dances held around a fire. Indeed, these people seemed to have spent much of their time naked, ignoring the heat and cold and claiming to be in the state of innocence enjoined by Adam and Eve."
1169px-The_arrest_of_Adamites_in_a_public_square_in_Amsterdam._Etch_Wellcome_V0035701.jpg
 
I am familiar with dangerous things you can take for weight loss, but not people are taking dangerous drugs for weight gain? I do not understand it.

Apetamin is an appetite stimulating weight-gain supplement manufactured and sold by the Indian pharmaceutical company TIL Healthcare. It is a syrup containing cyproheptadine (a hepatotoxin), lysine and some vitamins.

Apparently it is a social media thing, and they are selling it illegally on places like Amazon, Instagram and Depop.
There are loads of nice and "healthy" ways to put on weight, why get an illegal drug on the interwebs?
 
There are loads of nice and "healthy" ways to put on weight, why get an illegal drug on the interwebs?

A part of it is in the article, I'd say:
"I was told taking the Apetamin would only make me gain weight around my bum and my hips and my thighs - to be honest with you, it's quite daft of me to think that," another young woman says.


I also don't understand it myself, coming from a family where everyone is too thick.
But then I look at my brother-in-law, who is a stick. He doesn't like sweets, he doesn't gain weight, he lost weight over Christmas. He started going to the gym to put on some weight, and also that failed. He's underweight, and if you look at him, you'll probably think that yourself too.
So... I guess there are really people struggling with too little weight.
And I hate them soooo much :mad:.
 
Weight-gaining sucks. Take it from someone who used to weigh just 55 kilograms when he was 18.
It is actually quite easy for me to gain weight. And I hate it :)
 
Apparently it is a social media thing, and they are selling it illegally on places like Amazon, Instagram and Depop.
I wouldn't buy any 'medicines' from a website called "Depop" :shake:

(and no, I don't care what that website/app is actually for, nor what the founders thought they meant by the name)
 
Take it from someone who used to weigh just 55 kilograms when he was 18.

That's close to my current weight now and that's after I inexplicably put on weight over lockdown for the first time in literal years.
 
My body mass used to be closest to that of Eritrea. Now it's probably closer to Ethiopia.
 
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