Pretty sure he was not when I posted my comment. It currently says "more on him at the end" and that bit seems not to have been written yet. Also there are two mathematicians called "John Conway" so it's good form to say "John H Conway".
Author here, good call! I credit Conway in the center of the article, the content for "more on him at the end" was hidden after reader finish the challenge in part 6. I guess it worth to show it by default, updated already.
I'd also need to thanks for Dr. Arthur Benjamin. I saw his "That math show" with my 9 years old where he introduced this Doomsday rule, I thought it was really cool and try to create some interactive tutorial for it. Would love to see if this can help other kids or adults https://www.thatmathshow.com/
Cool site! When I do this trick I prefer using Bob Goddard's 'first Sunday' method [0]. It minimises the number of operations you need to do and makes it so you only need to keep track of one running total.
I can’t decide whether I find the AI writing or AI design more offensive.
Laughable that the footer has the stereotypical “made with <3” tagline (because of course AI has to use an emoji instead of words), for a site that almost certainly took less time to prompt than it takes to read it.
I know this is flagged, and I know the guidelines say not to complain about tangential annoyances, but the reason given is that "they're too common to be interesting" -- but is that true about LLM-written articles? A case could be made that it will only become more true if nobody objects.
I don't know what it is about LLM writing style, but I agree, it just triggers something in my brain and I can't get myself to read it.
I’d also suggest that when the user guesses wrong and you show the “correct” working, also continue to show the date so they can work it through correctly. The date changes right away so you can’t rework it and understand your mistake.
It's cool.
Here a little different way to calculate.
Day number + month number + year number, modulo 7 => weekday number.
Year number this year is 3, goes +1 every year, +2 in leap year.
Month numbers if not leap year: 033614625035.
Day number is ordinary day of the month.
24th Dec 2026 would be: 24 + 5 + 3 = 32. 32 mod 7 is 4 (Thursday)
I don't normally bother complaining about LLM writing, but this case is uncommonly bad. Everything above the fold is a nightmare. It's physically painful to see what's being done to English, my native language.
It lacks so much human guidance that it starts to veer into nonsense: "Suspicious? Check those dates against a real calendar." This doesn't make sense in this context. Those dates are examples produced by a computer, not the result of a person actually doing the trick.
Decades ago, I was reading about tricks, or as it was put, a systematic approach to do arithmetics without a pen. Those were paid courses.
It should have been obvious by then how irrelevant the whole thing was, since calculators with all kinds of shapes and forms were already widely available.
When you look at this page, there is a fair amount of memorization needed to make it somewhat useful. Then you don't want to make any mistakes in any of the steps.
That is a very roundabout way to say that I am fairly confident that nobody is actually going to "learn" what's in the page and apply it in realistic situations, and it's a complete waste of electricity to vibe code this page.
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[ 0.23 ms ] story [ 13.7 ms ] threadI'd also need to thanks for Dr. Arthur Benjamin. I saw his "That math show" with my 9 years old where he introduced this Doomsday rule, I thought it was really cool and try to create some interactive tutorial for it. Would love to see if this can help other kids or adults https://www.thatmathshow.com/
[0] https://firstsundaydoomsday.blogspot.com/2009/12/quick-start...
Laughable that the footer has the stereotypical “made with <3” tagline (because of course AI has to use an emoji instead of words), for a site that almost certainly took less time to prompt than it takes to read it.
I don't know what it is about LLM writing style, but I agree, it just triggers something in my brain and I can't get myself to read it.
When i do the 31/OCT, the solution show 10/10 as nearest squadday, i though 11/7 is the nearest ?
Isn't this very confusing to anyone outside US?
I get why it defaulted to this format, but in this day and age - it's trivial to automatically adjust it to the user's localization / preferences.
I’d also suggest that when the user guesses wrong and you show the “correct” working, also continue to show the date so they can work it through correctly. The date changes right away so you can’t rework it and understand your mistake.
A bit more guidance there would go a long way.
It lacks so much human guidance that it starts to veer into nonsense: "Suspicious? Check those dates against a real calendar." This doesn't make sense in this context. Those dates are examples produced by a computer, not the result of a person actually doing the trick.
I want to cry.
It should have been obvious by then how irrelevant the whole thing was, since calculators with all kinds of shapes and forms were already widely available.
When you look at this page, there is a fair amount of memorization needed to make it somewhat useful. Then you don't want to make any mistakes in any of the steps.
That is a very roundabout way to say that I am fairly confident that nobody is actually going to "learn" what's in the page and apply it in realistic situations, and it's a complete waste of electricity to vibe code this page.