prime-number-theorem by Ciro Santilli 40 Updated 2025-07-16
Consider this is a study in failed computational number theory.
The approximation converges really slowly, and we can't easy go far enough to see that the ration converges to 1 with only awk and primes:
sudo apt intsall bsdgames
cd prime-number-theorem
./main.py 100000000
Runs in 30 minutes tested on Ubuntu 22.10 and P51, producing:
Figure 1.
Linear vs approximation plot
. and are added to give a better sense of scale. is too close to 0 and not visible, and the approximation almost overlaps entirely with .
Figure 2.
. It is clear that the difference diverges, albeit very slowly.
Figure 3.
. We just don't have enough points to clearly see that it is converging to 1.0, the convergence truly is very slow. The logarithm integral approximation is much much better, but we can't calculate it in awk, sadface.
But looking at: en.wikipedia.org/wiki/File:Prime_number_theorem_ratio_convergence.svg we see that it takes way longer to get closer to 1, even at it is still not super close. Inspecting the code there we see:
(* Supplement with larger known PrimePi values that are too large for \
Mathematica to compute *)
LargePiPrime = {{10^13, 346065536839}, {10^14, 3204941750802}, {10^15,
     29844570422669}, {10^16, 279238341033925}, {10^17,
    2623557157654233}, {10^18, 24739954287740860}, {10^19,
    234057667276344607}, {10^20, 2220819602560918840}, {10^21,
    21127269486018731928}, {10^22, 201467286689315906290}, {10^23,
    1925320391606803968923}, {10^24, 18435599767349200867866}};
so OK, it is not something doable on a personal computer just like that.
X-10 Graphite Reactor by Ciro Santilli 40 Updated 2025-07-16
This was an intermediate step between the nuclear chain reaction prototype Chicago Pile-1 and the full blown plutonium mass production at Hanford site. Located in the Oak Ridge National Laboratory.
Figure 1.
Exterior of the X-10 Graphite Reactor in 1950
. Source.
Figure 2.
Workers loading Uranium into the X-10 Graphite Reactor with a rod
. Source.
Fusion power by Ciro Santilli 40 Updated 2025-07-16
Video 1.
Why Private Billions Are Flowing Into Fusion by Bloomberg (2022)
Source.
It is interesting that there are several different approaches to the problem. This feels a bit like quantum computing's development at the same time, increases hope that at least one will work.

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