# arc length of parabola

## Primary tabs

Defines:
universal parabolic constant
Synonym:
closed-form arc lengths
Type of Math Object:
Example
Major Section:
Reference
Parent:
Groups audience:

## Mathematics Subject Classification

### Crash of PM system

Are all articles made after November lost forever? There are no backups of them? Must the writers write the lost articles anew?
Now it seems that the new system does not allow to edit elder articles.
Jussi

### Re: Crash of PM system

There are no backups. Sadly the last backup was 2011-10-23. They exist in the sense that the authors might (should) still have copies, and copies might exist in various web caches (such as Google).

The editing problem should be fixed now.
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