URL for File Attachment

We have a table that is setup to allow a file attachment (PDF) to the record created (no separate table for attachments in this case).  We would like to be able to directly link to the uploaded file somehow.  I have created a formula to do this, but the path being output is displaying an error when attempting to access it. 
The URL from the formula matches the file URL up until the Record ID, where the QB record ID is numeric, the URL to the file is showing an alpha-numeric value.
Anyone know what is generating the alpha numeric ID in this case?

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Jason Hartwig
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