Showing posts with label Halloween. Show all posts
Showing posts with label Halloween. Show all posts

Monday, October 31, 2022

Happy Halloween and Happy Birthday, HP 42S

Happy Halloween and Happy Birthday, HP 42S








The HP 42S calculator was released to the market on October 31, 1988.  


I also want to wish you a safe and Happy Halloween.  Thank you.


Eddie 


All original content copyright, © 2011-2022.  Edward Shore.   Unauthorized use and/or unauthorized distribution for commercial purposes without express and written permission from the author is strictly prohibited.  This blog entry may be distributed for noncommercial purposes, provided that full credit is given to the author. 


Sunday, October 31, 2021

Happy Halloween: Belphagor's Prime and Triple Digit Integers

 Happy Halloween: Belphagor's Prime and Triple Digit Integers


Greetings everyone.  And a very Happy Halloween to you, hopefully you are all celebrating, having a great time, staying safe and sane.   


Today, I'm going there, talking about a number with a very dark and evil repetition, better known to religions as the "number of the beast":  six hundred and sixty six.  And to try to balance things out, I'm also going to be talking about a holy number.  


A Prime Evil:  Belphegor's Prime - Starring the Triple Six 


Belphegor's Prime is a large palindrome number:


1000000000000066600000000000001


that has three sixes in the middle of 13 zeroes on other side enclosed by a 1.  A two for one deal, not only the number of the beast but also the presence of a number with a unlucky repetition, 13.  Engineer and mathematician Harvey Dubner determined this monster of a number to be a prime integer.   However, the number received its nefarious name from well-known mathematics and science author Cliff Pickover.   


Who is Belphegor?   In religion, Belphegor is a prince of Hell, whose purpose in demonhood was to trick people into discovery (with a heavy price attached).  


Other connections to the infamous triple six include:


* The sum of the integers 1 to 36.  


* Multiply 2/3 by 1000 and take the integer part (without rounding) to get this number.


*  The triple six can be written has every roman numeral less than 1,000.  


*  It make can property very valuable, such as 666 5th Ave in New York City selling for a then record $1.8 billion, only to be changed to 660 5th Ave sometime later.  

 


Triple Digit Integers - The Glory of Triple Seven


Triple sixes aren't the only number to receive a mythological, metaphysical, or religious repetition.   


For instance, triple sevens, 777, is said to be a very heavenly number.  In Christianity, 777 represents the perfection of Trinity, made up of the Father, Son (Jesus Christ), and the Holy Spirit.  


Maybe the prime factorization of 777, 3 × 7 × 37, is what lead Judaism to declare the numbers 3 and 7 to be "perfect".


Finally, 777 is what brings much happiness to slot players. If you have been a casino, you know why. 


In numerology, triple numbers are promoted to have significance in the new age religion.  111, 222, 333, and so on, are given various meanings depending on the new age writer.  111 and its four digit number "relative", 1111, are very popular in the new age industry, often suggesting completion, oneness with the universe, and positive attraction thoughts. 


Generating Triple Digit Palindrome Numbers


You can generate integers 1 [ n number of zeros ] ddd [ n number of zeroes ] 1, where d is the digit 0 through 9 through the following formula:


10^(2n+4) + d × 111 × 10^(n+1) + 1


Examples:


n = 1, d = 9:   1099901


n = 2, d = 2:   100222001


n = 3, d = 3:   10003330001



No guarantees that the integer you get is prime.  Use at your own risk.  


Sources:


Grundhauser, Eric.  "How a Mathematician Turned an Obscure Number Into a Scary Story"  Atlas Obscura.  August 23, 2016.   Accessed August 1, 2021.  https://www.atlasobscura.com/articles/how-a-mathematician-turned-an-obscure-number-into-a-scary-story


"660 Fifth Avenue".  Wikipedia Last Edited. August 11, 2021.  Accessed August 11, 2021.  https://en.wikipedia.org/wiki/660_Fifth_Avenue


"666 (number)" Wikipedia.  Last Edited July 31, 2021.  Accessed August 9, 2021.  https://en.wikipedia.org/wiki/666_(number)


"777 (number)" Wikipedia.  Last Edited August 6, 2021.  Accessed August 9, 2021. https://en.wikipedia.org/wiki/777_(number)


Three very infamous tarot cards: The Tower, The Devil, Death.  (Gilded Tarot Deck - Ciro Marchetti)

Happy Halloween,


Eddie


All original content copyright, © 2011-2021.  Edward Shore.   Unauthorized use and/or unauthorized distribution for commercial purposes without express and written permission from the author is strictly prohibited.  This blog entry may be distributed for noncommercial purposes, provided that full credit is given to the author. 


Thursday, October 10, 2019

HP 41C/DM 41: Halloween and Thanksgiving - Calendar Calculations

HP 41C/DM 41:  Halloween and Thanksgiving - Calendar Calculations

Introduction 



We are about to enter the annual holiday season, and it's can be hard to remember when all the holidays.  Here is a way to determine what date Thanksgiving will be on this year, and all you have to know is what day of the week Halloween falls on.

Halloween is celebrated on October 31.  Halloween is celebrated on a fixed date, while Thanksgiving is celebrated on a fixed day of the week.

In the United States, Thanksgiving is on the fourth Thursday in November.  Therefore the only dates Thanksgiving in the United States is between November 22 and November 28.

In Canada, Thanksgiving is on the second Monday in October, which lands the possible dates between October 8 and October 14. 

Determine The Date of Thanksgiving Knowing What Day of the Week Halloween Is On

The first step is to give each day a numeric value:

Sunday: 0
Monday:  1
Tuesday:  2
Wednesday:  3
Thursday:  4
Friday:  5
Saturday:  6

To determine what date Thanksgiving falls on in the United States:

1.  Let H be the numeric value for the day Halloween falls on (see the above chart). 
2.  Subtract 4 from H.
3.  If the result is zero or negative, add 28; otherwise, add 21. 

Note:  The following programs could address alternative approaches given what the command set of the HP 41C/DM 41 allows us to do. 

HP 41C/DM 41 Program:  H>T

01 LBL^T  H>T
02 4
03 X<>Y
04 -
05 X>0?
06 GTO 01
07 7
08 +
09 LBL 01
10 21
11 + 
12 RTN

To determine what date Thanksgiving falls on in Canada:

1.  Let H be the numeric value for the day Halloween falls on (see the above chart). 
2.  Subtract H from 7. 
3.  Subtract 3 from the last result.
4.  If the result from Step 3 is zero or negative, add 14; otherwise, add 7.

HP 41C/DM 41 Program: H>CT

01 LBL^T H>CT
02 7
03 X<>Y
04 -
05 3
06 -
07 X>0?
08 GTO 01
09 7
10 +
11 LBL 01
12 7
13 + 
14 RTN

Now, let's go the other way.

Determine The Day of the Week Halloween Knowing the Date of Thanksgiving

The first step is to give each day a numeric value:

Sunday: 0
Monday:  1
Tuesday:  2
Wednesday:  3
Thursday:  4
Friday:  5
Saturday:  6

To determine the day of the week Halloween falls on given the date of Thanksgiving (United States):

1.  Let T be the date of Thanksgiving.
2.  Subtract 21 from T. 
3.  Subtract the result from Step 2 from 4.  If the number is negative, add 7.  See the above chart to determine the Day of the Week.

HP 41C/DM41 Program:  T>H

01  LBL^T T>H
02 21
03 - 
04 4
05 X<>Y
06 -
07 X<0 font="">
08 GTO 01
09 RTN
10 LBL 01
11 7
12 + 
13 RTN

To determine the day of the week Halloween falls on given the date of Thanksgiving (Canada):

1.  Let T be the date of Thanksgiving.
2.  Subtract T from 11.  If the result is negative, add 7.  See the above chart to determine the Day of the Week.

HP 41C/DM41 Program:  CT>H

01 LBL^T CT>H
02 11
03 X<>Y
04 -
05 X<0 font="">
06 GTO 01
07 RTN
08 LBL 01
09 7
10 +
11 RTN

Are you ready for the holiday season?  I'm not sure I am.  Let's have fun,

Eddie

All original content copyright, © 2011-2019.  Edward Shore.   Unauthorized use and/or unauthorized distribution for commercial purposes without express and written permission from the author is strictly prohibited.  This blog entry may be distributed for noncommercial purposes, provided that full credit is given to the author.

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