I heard here that Collatz conjecture was checked at least for every first $5 \cdot 10^{18}$ natural numbers, but I cannot find any source or actual information about this. Can anyone help to find out up to which number (or factor of 10
) we can now say that Collatz Conjecture is definitely true?
[Math] For how many consecutive numbers Collatz conjecture was checked
collatz conjecturecomputational mathematics
Best Answer
The following published paper gives $20\times 2^{58}\approx 5.7646\times 10^{18}$:
Tomás Oliveira e Silva, "Empirical Verification of the 3x+1 and Related Conjectures." In "The Ultimate Challenge: The 3x+1 Problem," (edited by Jeffrey C. Lagarias), pp. 189-207, American Mathematical Society, 2010.
The author's website suggests ongoing work, but the sublink is down.