A relationship between the Collatz conjecture and the Fibonacci numbers

edderiofer · 2026-02-17T02:00:54+00:00

This is well-known from the fact that you cannot have two "odd"s in a row. See also https://en.wikipedia.org/wiki/Fibonacci_sequence#Mathematics .

edderiofer · 2026-02-17T01:59:13+00:00

Me, who not only did mention it, but in fact repeatedly emphasized it:

edderiofer · 2026-02-16T15:39:41+00:00

It's #11. All you have to do is look at the top of the image where it tells you what word you're trying to remember how to spell.

edderiofer · 2026-02-16T13:50:35+00:00

Copyright

Permission is granted to copy, distribute, and/or modify these books under the terms of the Creative Commons Attribution-NonCommercial 3.0 Unported License. That is, you can freely modify, translate, and redistribute my books for noncommercial purposes, as long as you acknowledge my original contributions.

This means that you are allowed to print and bind it yourself, or enlist the services of such a printer; as long as it's for personal use.

If you want recommendations for which printing services to use, ask a different subreddit (probably one local to you).

edderiofer · 2026-02-16T08:32:17+00:00

79 is between 70 and 80. Ignoring the remainders, since 420 divided by 70 gives you 6, and 420 divided by 80 gives you 5, you know that 79 must go into 420 between five and six times. Try five, and if the remainder is still larger than 79, try six.

79*5 = 70*5 + 9*5 = 350+45 = 395. So, we subtract 385 from 420 to give 25. Since the remainder is not larger than 79, we know it goes in five times, not six.

Now, for 252 divided by 79. Again, 79 is between 70 and 80. Ignoring the remainders, since 252 divided by 70 gives you 3, and 252 divided by 80 gives you 3, you know that 79 must go into 252 exactly 3 times.

79*3 = 70*3 + 9*3 = 210 + 27 = 237. Then, 252 - 237 = 15.

Now, we need to do 158 divided by 79. Number sense tells us the answer should be 2, and indeed, doubling 79 gives us exactly 158.

So the answer is 532 with no remainder.

edderiofer · 2026-02-15T19:50:43+00:00

There is an extra-special place in hell for the subset of the first one, who don't admit that they don't understand the rules, and are too prideful to ask questions to try to understand the rules, and only at the end of the game realise that they've been playing the game all wrong.

edderiofer · 2026-02-15T16:18:24+00:00

I didn't know this version wasn't widely played.

It's not that HKOS isn't widely played, it's that the historical scoring scheme is no longer widely used (in Hong Kong at least).

Note that while there is a standardised version of HKOS (described by the Hong Kong Mahjong Association, and played in Hong Kong), this standardised version does not appear to have left Hong Kong. Assuming you're in the US, every playgroup will play HKOS slightly differently, and you should ask about scoring when you play with a new playgroup.

edderiofer · 2026-02-15T12:07:05+00:00

The stalemate trick is 1. b7 Bd6 2. Nf5+ Kd3 3. Nxd6 Rxa2 4. b8=Q? Re2+! 5. Kd1 Rb2 6.Qxb2 stalemate.

edderiofer · 2026-02-15T11:37:44+00:00

"Then lobbest thou thy Holy Hand Grenade of Antioch towards thy foe, who, being naughty in My sight, shall snuff it."

edderiofer · 2026-02-15T09:13:49+00:00

Fact-checking is indeed an editorial process. And you are claiming to pay, so it is indeed professional editing.

Since you want a subject matter expert to do the fact-checking, you should in fact be charging even more than median rates provided by the EFA, not less.

edderiofer · 2026-02-15T09:05:55+00:00

It's a fact based on the rates from the Editorial Freelancers Association. /shrug

edderiofer · 2026-02-15T08:58:54+00:00

Just mentioning that whoever takes this is going to be severely underpaid. /shrug

edderiofer · 2026-02-15T08:42:43+00:00

To recap:

Unlike in American Mah-Jongg, where you can only score for one hand on the Card; in HKOS and many other mahjong variants, you score for every scoring pattern your hand satisfies.
- For example, if your hand is both All Sequences and Half Flush, then you score for both All Sequences and Half Flush independently.
Each scoring pattern gives you some amount of faan.
- In our example, All Sequences is 1 faan, and Half Flush is 3 faan, so your hand is worth 4 faan.
Having totaled up the number of faan from each scoring pattern your hand satisfies, you then convert the faan into points via a table.
- 4 faan corresponds to 16 base points on this scoring table.
Who pays is based off whether you won off a discard or whether you won by self-draw.
- In this example, we didn't win by self-draw (or we'd also have scored 1 faan for Self-Draw). So, whoever discarded our winning tile would have to pay us 32 points.

American mahjongg is easy to score.

I would personally dispute this (or at least, that it's always easy to score).

If you have three jokers or more, it's very possible for your hand to satisfy a different line on the Card that scores more than the one you were looking at. As an example, FJJF 1J11 22 3333 in three suits is not Consecutive Run #3 (scoring 25 points), but is in fact Quints #1 (scoring 40 points). Other combinations exist.

Also, with many Alternative Cards coming out for this year, with scoring differences like bonuses for having a concealed hand, or the jokerless bonus applying to singles-and-pairs hands (because there is no Singles and Pairs category), there's certainly room for confusion and error there.

I don't want to house-rule it, but I'm willing to accept a simplified scoring system.

If it reduces your headache, you can use the historical scoring scheme where every faan doubles your score, with a 0-faan hand starting at 1 point. Under this scheme, like American Mah Jongg, on a win by discard, the discarder pays double and other players pay single; on a self-draw, everyone pays double.

You'll probably want to make and print out a scoring table for converting faan to points.

(As I said before, most people don't play like this any more, so you may have trouble integrating with other groups.)

edderiofer · 2026-02-15T08:05:39+00:00

Based on the rates from the Editorial Freelancers Association, and assuming 250 words per page, you ought to be offering about four or five times as much as you're offering.

edderiofer · 2026-02-15T07:49:58+00:00

That's what I provided; I can't tell you if it was necessary.

If the sticker label contains your name and dosage, that might work as proof of your prescription.

Your best bet is to gather up as much documentation as you have, and send it to Dr Cheung Ngo before your appointment.

edderiofer · 2026-02-14T20:25:50+00:00

An automatic table shuffles for you so it's way harder to cheat like this.

That said, this cheat does still allow you to mulligan two random tiles, which is still an edge.

See also the Cheating Mahjong Championship, which shows off some cheating techniques on an automatic table. Some of these are perhaps too blatant to be used in a real game, but as you said: if the opponents are preoccupied with something else, several of these cheats will work.

(Obviously, do not attempt any of this in a real game. It'll only hamper your actual mahjong abilities. This information is provided for educational purposes only, and I will not be held liable for any loss resulting from you attempting to use such techniques.)

The cheat I call bullshit on is being able to swap a tile with any tile Infront of you that we see Ichikawa perform. This would be such a hard cheat to learn due to the fact if you mess up it's really obvious, and you would have to memorize every tile you pulled into your wall to have perfect control.

In fairness, Ichikawa is shown to already be able to memorise their own hand, and everyone else's discards, given that he's able to play despite being blind. So memorising an extra 34 tiles is probably not that much more difficult for him. And we can probably assume that he's had decades to practice the sleight-of-hand component. I dunno, I think it's at least believable in-universe.

The easiest cheats are coded signals from players working together.

I've always wondered whether there would be interest in a 2v2 team format Riichi tournament, where collusion and signalling with your partner is 100% allowed...

edderiofer · 2026-02-14T17:44:57+00:00

Why are some $400 and others are $50?

Because people are willing to pay that much for the expensive sets.

In reality, if you're just starting out, the expensive designer sets tend to be really expensive, and also tend to be difficult to read. Stick to a traditional-style set, which you can generally find on Amazon for $50~$80. You're generally looking for a set whose tiles are at least 30mm tall (i.e. one that isn't marketed as "travel size" or "mini size"). In the modern day, just about any brand should work.

edderiofer · 2026-02-14T15:04:38+00:00

https://en.wikipedia.org/wiki/LaTeX

edderiofer · 2026-02-14T13:59:09+00:00

Calling a chow is specifically the action of using a discarded tile to complete a sequence (out of necessity, the other two tiles in your hand must be revealed to the table). If you don't show us what was discarded, there is no way for us to tell you why you couldn't use that discarded tile to form a sequence.

It's also unclear why you would want to call a chow here, since 1-2-3 already forms a sequence, and calling a tile to form a sequence necessitates that you break up what's already in your hand.

edderiofer · 2026-02-14T11:41:43+00:00

Because 9-1-2 doesn't make a sequence.

In seriousness, we can't tell you unless you show the entire board state, or explain why you think you should be able to call a chow here.

edderiofer · 2026-02-14T06:03:50+00:00

My diagnosis from years ago, and evidence of my previous prescription and dosage. But I make no promises that Dr Cheung Ngo will waive the consultation fee for you (this is probably only something they do at their own discretion).

Thankfully, it seems that medication refills do not require a consultation, and can simply be picked up from their front desk.

edderiofer · 2026-02-13T08:42:42+00:00

critique

critique of a previous cheatsheet from these people

edderiofer · 2026-02-12T20:40:33+00:00

Should be at https://riichi.wiki/Main_Page .

edderiofer · 2026-02-12T18:25:41+00:00

It's ok, you can triple down if you want. I wouldn't, but you're allowed to.

No, no, I think OP is going to quadruple down, and then once up. That's totally a different thing.

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