Syracuse numbers

Computes Syracuse numbers, also called 3n+1 conjecture : let's start with any number N, and apply following rule : if N is even N=N/2, if not N=3N+1.
It seems that N will always drop to 1...but is it true for *any* value??? Nobody prooved it!

With this page you can try to find a new record (or a N value proving this conjecture is false) by using any starting N as big as you want : enter a value, and click on the button "go for syracuse". You can also automatically search for records by choosing N and clicking on "search for max height" or "search for max length" buttons, good luck :)

show details hide during loops
Search for max height : delta:
Search for max length : delta:

Some high scores : N=104899295810901231 needs 2254 iterations (Eric Roosendaal), no n < N has more iterations.
Thr first N with 2000 iterations : N=377060271667498687 N=67457283406188652 (more details on Eric Roosendaal's «Class Records» page).

Some high links : wikipedia, Eric Roosendaal, Eric Farin, ...


Best result: