2020 gone for good. Welcome 2021!

[Gerson W. Barbosa]

[Dave Britten]

20201231 and 20210101 are both prime numbers. Maybe it's a good sign...

[rprosperi]

Awesome job Gerson, I LOVE seeing the New Year greeted by an HP-75C!!

And something about the fact that both of those number are Prime, and even more so that Dave thought to check their primeness, bodes well for a better year.

Happy New Year everybody!

[Gamo]

Happy New Year 2021

[attachment=8975]

Gamo

[Massimo Gnerucci]

Something terribly wrong must've happened here!
   

Happy (new) year!

[DA74254]

Happy New Year. Welcome 2021.

[Sylvain Cote]

Happy New Year!

[MNH]

Happy New Year 2021!

[attachment=8977]

[Valentin Albillo]

(01-01-2021 04:39 AM)Dave Britten Wrote:  20201231 and 20210101 are both prime numbers. Maybe it's a good sign...

Indeed they are. As for 2021, it's composite and readily factorized a la Fermat, like this:

            2021 = 2025 - 4 = 45² - 2² = (45 - 2) * (45 + 2) = 43 * 47.


Happy New Year 2021 !

V.

[Nihotte(lma)]

Happy New Year 2021 !

Laurent

[twoweims]

(01-01-2021 04:39 AM)Dave Britten Wrote:  20201231 and 20210101 are both prime numbers. Maybe it's a good sign...

This will not be true next year...
I wonder how often this happens and when will be the next time?

[Jlouis]

Happy NEW YEAR !!!
Stay safe, protect the ones you love and the ones you don't love too! Love all!

P.S.: I have a feeling that I made a mistake in the picture above, but I cannot find which.....never mind....

[twoweims]

(01-02-2021 01:28 AM)twoweims Wrote:  

(01-01-2021 04:39 AM)Dave Britten Wrote:  20201231 and 20210101 are both prime numbers. Maybe it's a good sign...

This will not be true next year...
I wonder how often this happens and when will be the next time?

My HP-71 says it happens at the end of these years:

Code:


 4                  
 103                
 160                
 190                
 211                
 271                
 304                
 346                
 367                
 376                
 451                
 475                
 502                
 550                
 586                
 649                
 736                
 799                
 817                
 874                
 937                
 1000               
 1018               
 1051               
 1084               
 1126               
 1153               
 1159               
 1165               
 1186               
 1198               
 1237               
 1468               
 1513               
 1555               
 1600               
 1621               
 1747               
 1810               
 1828               
 1891               
 1930               
 1972               
 1978               
 1987               
 2020               
 2029