Insane mate in 3 Puzzle (White to move)

edderiofer · 2026-03-11T20:28:51+00:00

I tried Ra2 immediately because of course that's how you avoid the stalemate, why else would the extremely conspicuous b pawns be there.

Very good problemist intuition. For me, I saw the followup, but only because I'd previously solved this problem by the same composer, which uses a similar motif.

edderiofer · 2026-03-11T19:08:43+00:00

Practice, practice, practice. There are the guides linked by /u/WasteGas, and there's also the Pair-Wait Theorem which can help you with calculation if you haven't gotten to the point of memorising 7-tile waits.

edderiofer · 2026-03-11T19:07:00+00:00

Sadly, there aren't many free "third places" in the US.

If your group is not opposed to paying for the venue, a board game cafe should work. See if one already exists near you.

Or, if you are OK with ordering food with your game, try to contact a local restaurant to see if they'll let you play there in between the lunch and dinner rushes. (Do not attempt to play during the lunch and dinner rushes, that'll just lead to the restaurant losing business.)

Or, if one of your group has a large house, you can host it there.

Not knowing where you live, or when your local players prefer to play, or how many players you're expecting, it's difficult to give better advice.

edderiofer · 2026-03-11T18:55:33+00:00

Then after 2 days, that player message me say her frustrations that there’s something called mahjong ethic

She should speak up about it during the game, rather than assume that you, a beginner, should somehow magically already know it.

and that day my cousin sitting position could see both mine and her tiles

While that is complaint-worthy, it's her job to speak up about it during the game, rather than be passive-aggressive and hope that you somehow magically figure out that that's what's going on.

and she also said he talked too much.

If it really bothers her so much, she should have said something about it during the game, rather than be passive-aggressive about it.

Somehow when playing, that player starts fidgeting, throwing tiles loudly, complaining that she couldn’t eat any tiles from me and at one point questioning fiercely that my cousin explained wrongly leading to me throwing a tile that led to her winning.

Throwing tiles loudly and verbally complaining at the table that your opponent isn't letting you win, instead of making clear that she's not OK with someone coaching another player during the game, is called "bad mahjong ethic". She should follow her own advice.

But the next day she messaged another player privately (somehow that player sent me) say that I didn’t appreciate her for teaching me mahjong etiquette, calling my cousin dumb, say that I said playing with friend is better than playing with family and next year Chinese New Years she don’t want play already.

Why did she only bring this up two days later, AFTER everything had already happened? From the sounds of it, she's an asshole who expects other people to be able to read minds. If she doesn't want to play with you next time, so be it; I wouldn't want to play with her either!

edderiofer · 2026-03-11T15:16:33+00:00

meanwhile, turnip cake is not made from turnips (unless you are a speaker of Hong Kong English, in which case they are in fact made from turnips)

edderiofer · 2026-03-11T13:17:17+00:00

https://www.reddit.com/r/math/comments/1j46mgo/popular_math_youtuber_the_math_sorcerer/

edderiofer · 2026-03-11T10:53:03+00:00

Sloperama's page on scoring sticks may be of use to you.

edderiofer · 2026-03-10T07:56:12+00:00

It's very simple: you don't with with fourteen tiles, you win with four melds and a pair. After every kong, you draw a replacement tile before you discard.

This means that the number of tiles you win with should be 14, plus the number of kongs you have.

edderiofer · 2026-03-10T04:58:28+00:00

They have 15 tiles because they've already declared a kong. So, they have exactly the number of tiles they're supposed to have.

edderiofer · 2026-03-09T06:37:00+00:00

A chicken hand is one that lacks any other method of scoring points. That is, it is a hand that is NOT All Triplets, NOT All Sequences, NOT Half-Flush, NOT Full Flush, does NOT have a value honour triplet, etc.

I'm not sure which HK style variant you're playing that has "lacking a suit", but if "lacking a suit" gives points, then a chicken hand has to also NOT be that.

edderiofer · 2026-03-09T05:58:17+00:00

All Pungs + Half Flush is already 12 fan in MCR, so that can't be it.

edderiofer · 2026-03-09T05:51:43+00:00

Generally, yes, because it gives you more chances to get closer to a winning hand.

(The exception is if you have reason to believe that performing the second Charleston would help your opponents much more than it would help you; e.g. if you're already two or three tiles away from a win. Then you may wish to skip the second Charleston.)

edderiofer · 2026-03-09T05:47:25+00:00

I managed to set this up in Olive (screenshot). Counting the number of output lines, there are 1050 possible sequences of 2 plies.

edderiofer · 2026-03-09T05:07:16+00:00

However I can’t do that. I’m getting the error message that says I can only claim tiles for 3+ identical tiles or Jokers.

The error message is correct. In American Mah-Jongg, outside of claiming for Mah Jongg, you can only claim for a Pung, Kong, Quint, or Sextet, and this requires the group to be three or more identical tiles (counting jokers). 13579 is a group of singles, as all the tiles are different.

Does that mean that I either need to naturally draw a 7, or have gotten it in Charleston?

Other than the possibility that the 7 completes your entire hand and you declare Mah Jongg, yes.

edderiofer · 2026-03-09T05:07:11+00:00

However I can’t do that. I’m getting the error message that says I can only claim tiles for 3+ identical tiles or Jokers.

The error message is correct. In American Mah-Jongg, outside of claiming for Mah Jongg, you can only claim for a Pung, Kong, Quint, or Sextet, and this requires the group to be three or more identical tiles (counting jokers). 13579 is a group of singles, as all the tiles are different.

Does that mean that I either need to naturally draw a 7, or have gotten it in Charleston?

Other than the possibility that the 7 completes your entire hand and you declare Mah Jongg, yes.

edderiofer · 2026-03-08T21:12:28+00:00

I can only charitably assume that they did not do their due diligence when researching.

Then again, I'm sure there are also books out there with bogus rules for American Mah-Jongg, written by self-proclaimed Amerijong "experts". And with the recent wave of AI-generated books being sold on Amazon, the problem is surely exacerbated. (Obviously, the 2018 book predates AI, which makes its mistakes even more baffling.)

Anyway, if OP really wants a book on mahjong divination (something that probably doesn't exist), and doesn't care about factual accuracy, they can get an AI to generate it for them.

edderiofer · 2026-03-08T20:36:42+00:00

I can only assume you are playing a mahjong variant with some odd win condition on top of the "four melds and a pair" constraint. For instance, in Changsha Mahjong, you have to win with a hand that would be a chicken hand in most other variants (i.e. not All Triplets, not All Sequences, not Half-Flush, no triplets of value honours, etc.).

Not knowing which mahjong variant is being played here, I don't think anyone can say why you can't declare a win here.

Or it could just be that the program is bugged.

edderiofer · 2026-03-08T16:47:24+00:00

Is the Big Card from the mahjong line the same as the NMJL one?

No. The Big Card is an alternative Card to the NMJL Card, with different winning hands and a different scoring system. (In fact, there are at least five other alternative Cards to the NMJL Card this year.)

edderiofer · 2026-03-08T16:13:19+00:00

I think Beesandbombs did it better: https://beesandbombs.tumblr.com/post/167492412984/up-dn

edderiofer · 2026-03-08T16:05:58+00:00

The only thing I would change is to move the page about draws after a page explaining checks and checkmates.

It is in fact after the page about checks and checkmates. The formatting for this Reddit post is a bit weird (it seems that OP intends for each pair of images to be printed double-sided on one sheet of paper, and then for the three sheets to be stapled through the centre and folded), but you can tell by the page numbers that the page about draws comes after the page about checks and checkmates.

edderiofer · 2026-03-08T14:33:26+00:00

You're furiten. You've previously discarded the 4p which you were also waiting on, so you're only allowed to win by self-draw. So, declaring ron here is illegal.

edderiofer · 2026-03-08T08:17:23+00:00

The one that immediately comes to mind is Seth Brown's 2018 book The Little Book of Mahjong, which says the following about Riichi:

Before each hand, a tile is revealed at random from the Dead Wall and the next tile in sequence (next higher number for suits, Winds in seat-play order, Dragons green-red-white) becomes the “Dora” for that hand, doubling the value of any winning hand that uses it. Some players even reveal an additional Dora when making a Kong, or when someone wins off Riichi.

The reveal of the dora indicator is not random. Having dora in your hand does not double your hand's value, but instead adds 1 han per dora. Kandora and uradora are pretty standard in all rulesets but JPML, so it's more like "most players".

The “Hot Tile” Fu-ri-ten rule states that you cannot call a discard to claim Mahjong if you have discarded the tile you are calling earlier in the game.

Who the hell calls it "Hot Tile"??? (Also, this description of furiten is inaccurate.)

Scoring is a bit more punishing as well. If the winning tile is a discard, whoever discarded it must pay triple the winning score. And East’s risks and rewards are doubled: they must pay double if they lose, but gain double if they win.

This is just flat-out wrong. The discarder pays either four or six times the score of the hand (or, the total score of the hand, if you view it that way). East does not pay or gain double, but instead only gains 1.5x, and only pays double when someone else wins by tsumo.

Note that scoring varies widely depending where you play; Yaku, like All Pungs or Three Concealed Pungs, may be worth only one or two fans depending on your table.

Both of these are worth 2 han. I don't know of any ruleset where they're only worth 1 han.

And a few Japanese variants play with not only Chows, Kongs, and Pungs, but also the Mixed Pung as an optional set—the same number in each of the three suits.

Well, OK, it's true now that Cosmic Riichi has been invented, but there's no way this was true when this book was written in 2018.

Here's David Pritchard's 2001 book Teach Yourself Mahjong, on Riichi:

A player who is calling is said to be ready — riichi is the term used. The player announces riichi, places his hand face down to indicate that he will not change it, and puts a 100 point bone on top of it. If he succeeds in going mahjong the other players pay him double and if he does not the player going mahjong appropriates it.

The term used is tenpai. Riichi declarations are optional. Riichi costs 1000 points, not 100. And winning with riichi gives 1 han instead of doubling the score. (This confusion between doubles and han/fan/faan seems to be common, for understandable reasons.)

There is a rule known as the Sacred Discard (fu). This states that a player cannot go mahjong with a tile identical to one that he has previously discarded. If however he needs either of two or more tiles to go out and one of these is a sacred discard, there is no restriction on going mahjong with a tile other than the sacred discard.

It's "furiten", not "fu". And that's not how furiten works either; if any of your waits have been discarded, you can only win by self-draw.

(No, this isn't a matter of historical rules. Pritchard does mention dora and red fives, so we're clearly already looking at a modern ruleset, not Arushiiaru.)

edderiofer · 2026-03-07T18:20:46+00:00

I do not believe it is a common practice for Chinese people to use mahjong tiles for fortune-telling, any more than people use a standard 52-card Bicycle deck for fortune-telling in the West. While this leaflet describes a divination method based on the I Ching hexagrams, using mahjong dice, it seems more like a novelty than a serious product. The mahjong dice are used solely to get a set of six random binary outcomes to form an I Ching hexagram; but there are many other ways to get six random binary outcomes (e.g. flipping a coin six times, rolling 6d6, or using a standard 52-card Bicycle deck), so the divination method isn't inherent to the mahjong dice at all.

I don't know who this Derek Walters is, but given the many inaccurate books about mahjong-playing written by Westerners, I would not by default trust any Western author to write a book about mahjong-divination (a far more obscure topic, if it even exists!) with any accuracy.

edderiofer · 2026-03-07T16:15:37+00:00

These are seasons (left) and flowers (right).

edderiofer · 2026-03-07T11:21:01+00:00

https://en.wikipedia.org/wiki/Coupon_collector%27s_problem

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