Memorizing Dates and Days

Hello guys I have a really cool trick to memorize dates of each day of each month in a year in a really powerful way… Well first you need to have a mental image that represents each month forxample for me February is represented by a rose since it’s the “Month of Love”. The images are really at your discretion. Just anything that resonates with you…With this done, pick a day of the week that works as your linchpin and store it’s first occurance in the month. For me I use a Sunday. For example The first Sunday of February 2021 is 7th. So I store February 7th.
Later If I needed to know what the third Wednesday of February would be, I Simply decode my mental image of February and count up to get the first Wednesday which in this case is 3rd then simply add up 14 days to get the third Wednesday’s date. How cool is that?.. Let me know when it works for you

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I also use that trick, a way to memorize it better is creating a virtual room, for example I imagine February 2021 room’s walls full of roses and inside this room I put a grape (for me grape is the number 7).
I think this is a nice trick for beggining.

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Awesome

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That’s a pretty cool way to quickly learn how to tell the day for various dates.

If you’re curious about the standard method used by human calendars who can calculate dates from any century very very quickly, read about the Human Calendar Method. Some of us can calculate these in less than one second.

This method uses the same principle as yours, but has some optimizations.

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There is a method for finding the day of any year from year 1600-2100 and it is also called 500 years calender, It is free and made by a record holder and I think it is the simplest method if you will learn the table of 14 upto 15 times and will be able to put a zero there and then subtract the lesser value with the greater one(This will require some common sense but over time this will become natural in less than 10 attempts, It does not take a long time to divide a number 4 digit number by 140 and subtract it’s remainder using the Tracnchenberg system anyway and then to again quickly divide that remainder by 7 if its more than 7(The number of days in a week),

And I think that memorizing the Year and Month code in calenders is unnecessary there is a way to perform calander calculations without any code by finding the code for a date itself in 6 seconds and the remaining 5-6 seconds can be spent on adding the codes and dividing them,

Remember, so not divide a smaller number by a greater number or a two digit number by a 3 digit number,

And,

Cheers.

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That’s amazing I can do about 2 in sixty seconds

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did you memorize or calculated?

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Изчислява ги

@Josh

just in case it interests you…

I found your blog entry How to Calculate the Day of the Week from Any Date - Art of Memory Blog and struggled with the years code…

after working with the numbers a bit I found this pattern

I just did a few dates and it seems to work. For dates in january/february in leap year you still have to do the -1 manually.

Pattern A: consists of 16 numbers (years 00 - 15), reoccurs every 28 years
Pattern B: consists of 12 numbers, is the filler between Pattern A and also occurs every 28 years)

I don’t know if there’s an easy way to memorise this though

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Additional info: We can also mod the date code by 7

18.01.2021 would be either
DateCode+MonthCode+CenturyCode+YearsCode
18+0+6+5 = 18 + 11 = 29 mod 7 = 4 Rest 1
or
(18 mod 7 = 14 Rest 4) = 4+0+6+5 = 15 mod 7 = 2 Rest 1

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Have a look at the multiples of 12 if you want a pattern…

0*12=0
1*12=12
2*12=24
3*12=36

Since 3*4=12, you know that you’re looking at every third leap year and skipping over two each time. From a multiple of 12 (which is a leap year) to the next leap year is then “plus 5.” One for each year and one for the leap year.

E.g., 50

You know that 48 is the last multiple of 12 that is less than 50…

4*12=48; so you’re at 4 and then 2 more to get from 48 to 50.
4+2=\color{red}6; which is the year code for 50

E.g., 70

You know that 60 is the last multiple of 12 that is less than 70…

5*12=60; so you’re at 5 plus 5 plus 5 for two leap years
60 \to 64 \to 68; and then 2 more to get from 68 to 70.
5+5+5+2=17 mod 7 \to \color{red}3; which is the year code for 50

*feel free to mod7 the 10 (two leap years), that way it’s +5 for one leap year or +3 for two leap years.

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The “odd +11” method for calculating the day of the week is slightly easier for mental calculation because it has fewer steps in it. It’s described here but the basic idea starts with finding the day of the week of the last day in February for the year you’re interested in…

The last day in February is the same day of the week as:
4/4, 6/6, 8/8, 10/10, 12/12
5/9, 7/11, 9/5, 11/7 (mnemonic: “she works 9-5 at 7-11”)
plus the fourth of July, Halloween (10/31), and Boxing Day (12/26)
From there, you can quickly calculate for almost any day.

Details are in the Wikipedia article – good luck!

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I’m definitely going to have to try that!! Thanks :slight_smile:

how would you guys memorise the 100 year codes?

Saying
00 = 0
01 = 1
02 = 2
03 = 3
04 =5
05 = 6
06 = 0
07 = 1
08 = 3
09 = 4
10 = 5

brut force and spaced repetition?

IMHO; you need understanding.
A year has 365 days (if it is not a leap year).
365 = 350 + 14 +1, so 365 mod 7 = 1.
If that last part went too fast, 365 mod 7 = (350 + 14 + 1) mod 7 = (350 mod 7) + (14 mod 7) + (1 mod 7).
350 mod 7 = 0.
14 mod 7 = 0.
1 mod 7 = 1.

In normal English, a year consist if 52 weeks of 7 days, making 364 days. This leaves one extra day.

What this means is that if January 1st 2010 is a Friday, then January 1st 2011 is a Saturday and January 1st 2012 is a Sunday.

This is true, except for leap years. A leap year has 366 days. If 365 mod 7 =1, then 366 mod 7 = 2.

In normal English, the year code for a normal year is 1 and for a leap year (which has an extra day) is thus 2.

In the case of your list, we need to add these codes.
The first one is zero. So the next years will be 1, 2, 3. The 4th year is a leap year, so add 2 and the code is 5. Next year 6, 7.
The code 7 is also 0 (7 mod 7 = 0).
So now we have 0, 1, 2, 3, 5, 6, 0.
Next year add one: 1
Next year after that is again a leap year, so add 2 (to 1) = 3.

Now the formula:
Take the year number and add the year divided by 4 (integer division).
Let’s take the symbol ‘’ to denote integer division.
23 \ 4 = 5. (23 / 4 = 5 3/4, so integer is 5).

Now the formula becomes: year + year \ 4.

So the year 10 becomes 10 + 2 (10 \ 4 = 2).

We can now expand the list:

So let’s take 29: 29 + 29 \ 4 = 29 + 7 = 36. 36 mod 7 = 1.

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I memorised year codes by this approach -

  1. First I created memory palace that contains 7 rooms.
  2. Then I coded numbers (00 - 99) into words by my number system.
    Example - 23 - राम (ram), 82 - कार (car).
  3. In the end, I placed all numbers whose code is 1 in the first room of my memory palace.
    Code - 2 (in second room)
    Code - 3 (third room)
    Code - 4 (fourth room)
    Code - 5 (fifth room)
    Code - 6 (sixth room)
    Code - 0 (in last room)

Example - in your table of year codes.

01 = 1
So 01 - bat (and bat is placed in my first room)

I hope you understand my approach (how I memorized year codes of calendar.)

Hello, yes that approach is perfect for me.

I have a peg list in major system from 0(0) - 99 so I can convert the years into pegwords as well and store them in the correct room.

I’ll try that approach thanks!