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Proposed Release Schedule for New Problems

  • Problem 710 is scheduled for Saturday, 11th April 2020, 08:00 pm
  • Problem 711 is scheduled for Saturday, 11th April 2020, 08:00 pm
  • Problem 712 is scheduled for Saturday, 18th April 2020, 11:00 pm
  • Problem 713 is scheduled for Sunday, 26th April 2020, 02:00 am
  • Problem 714 is scheduled for Sunday, 3rd May 2020, 05:00 am
  • Problem 715 is scheduled for Sunday, 10th May 2020, 08:00 am

Recent News

28 March 2020: Daylight Saving Time

In contrast to previous years, the Project Euler release schedule will not observe the UK daylight saving time that is due to come in effect on Sunday 29th March 2020. From problem 709 onwards, release times will follow a pattern based on UTC. We hope this gives a more consistent experience for our international community.

14 October 2019: Maintenance Notice

On Tuesday evening 15 October 2019 (UK time), Project Euler will be inaccessible for maintenance due to an internal migration to a new VPS. Although we have been happy with the general performance on the current server, by moving to a more powerful server we are hoping that this will provide a stable environment for quite some time to come.

After the DB migration and testing has been completed it will be necessary to update the DNS on the VPS cluster. For most people this should happen quickly, but fully propagating throughout the global network means that some members may have to wait longer. Whilst your local DNS has not been updated you will continue to point at the old server, which will remain in maintenance status. So as soon as Project Euler appears to be back online you will know that your DNS has been updated; you will be on the new server and able to continue solving problems. Due to the way we are handling this there should be no data loss.

Whilst the main website is inaccessible we would remind you that a static version of the problems can be found at https://projecteuler.info. The problem set is up-to-date and although it will not update your profile, you are able to check answers. This link will appear on the maintenance notice page when it appears.

We hope that the move goes smoothly, but we would ask for your patience and understanding if we encounter any issues.

25 August 2019: DB Migration Issue

To keep the website running optimally it becomes necessary for our hosts to periodically migrate the DB to a new server. We are very grateful for their diligence in this matter and it has always happened in the past without incident. However, today it seems that some of the data on the new server became corrupt during the transfer. Consequently it was impossible to sign-in, giving the impression that your account no longer existed. Fortunately, all the data remained intact on the old server.

So once the issue had been reported our hosts were able to point the site back to the DB on the old server before carefully ensuring that all of the data was migrated properly this time.

We are very sorry for the inconvenience and the scare this might have caused some members when they thought for a moment that their accounts had disappeared.

The site is now pointing at the DB on the new server and it should all be working as expected. It is highly unlikely that any data has been lost during the migration, but if you solved any problems in the last day, then for your own peace of mind it is recommended that you check no progress has been lost.

20 August 2019: Pinning Problems

A change was made recently to the website that allows you to pin problems. This should be useful if you wish to return to a particular problem.

At the top of each problem page you will find a small icon in the top right corner allowing you toggle between pin/unpin. Once a problem is pinned the ID will appear in blue on the problems table page and it will be shaded blue on your Progress page. In addition, on the Archives page you can also filter problems by pinned. Please note that currently each member is limited to ten pins.

Hopefully this proves to be a useful addition to Project Euler. If you spot any issues, then please use the thread:
https://projecteuler.chat/viewtopic.php?f=5&t=6947

17 June 2019: Summer Break

Problem 677 on Saturday 29th June will be the last problem of this season. Project Euler will then take a summer break, returning with a new problem on Saturday 7th September.