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1.5 trillion digits of log(2)

Using y-cruncher, I calculated 1.5 trillion digits of log(2). The hardware used and its information are presented below:

supermicro_server.webp

Component Specification
Processor 2x Intel(R) Xeon(R) CPU E5-2690 v3 @ 2.60GHz
Topology 48 threads / 24 cores / 2 sockets
Usable Memory 252 GiB
Usable Storage ~200 TiB

I used Proxmox to manage an Ubuntu container allocated with the full server’s resources to easily structure and partition the server. Then, to meet Numberworld’s standards for record submission, I ran the calculation twice:

The first calculation used the Primary Machin-like Formula (3 terms) algorithm provided by y-cruncher. That is: log(2) = 18 ArcCoth(26) - 2 ArcCoth(4801) + 8 ArcCoth(8749).

The second calculation used the Secondary Machin-like Formula (4 terms) algorithm (also provided by y-cruncher) for verification. That is: log(2) = 144 ArcCoth(251) + 54 ArcCoth(449) - 38 ArcCoth(4801) + 62 ArcCoth(8749).

The results from these calculations matched, indicating that the computation was successful. The process was very storage intensive:

Algorithm Read Written Compute Time
Primary 737 TiB 647 TiB 96.4 days
Secondary 823 TiB 728 TiB 53.6 days

Over the course of the calculations, nearly 1.5 PiB (~1.5 million gigabytes) of data was read and written to the hard drives, causing many of the already-used disks to fail. Thankfully, I had expected some drive failures so I had partitioned the disks with RAID before starting the calculations.

Results

Below are the last digits that were computed (numbered 1,499,999,999,901 to 1,500,000,000,000), broken into groups of 10 for clarity:

5455756881 7640150407 6681972149 9106229418 4374409281
1670491330 6214376057 5948324637 0570636787 5000462651

Both full logs are available at the Numberworld website: computation log and verification log.

Aftermath

This computation held the record for the most digits of log(2) ever calculated, from September 9, 2021 until February 12, 2024 (for a total of 886 days), when Jordan Ranous successfully calculated 3 trillion digits of log(2) in just 90 hours! As of the time of this writing, the current record holder is Mamdouh Barakat with 3.1 trillion digits, announced on November 15, 2025.


Last updated June 22, 2026