These don't seem like legitimate requests; I say that as the "limit" is "1.81816816818E+14" which is throwing the error... It'd appear that invalid data is being passed as the page number in user requests...
Valid: https://www.ubbcentral.com/forums/ubbthreads.php/forums/3/1/bug-reports
Invalid: https://www.ubbcentral.com/forums/ubbthreads.php/forums/3/1.54/bug-reports (see the .)
Invalid: https://www.ubbcentral.com/forums/ubbthreads.php/forums/3/1238762837698623849762345/bug-reports (see the absurdly long page number)

Do you have legitimate users reporting problems with viewing forums, or are you simply just pulling information from SQL logs?

Its entirely possible that this is some bot that sees that the page id is fetched via a URL and is pinging every conceivable page for content, and at some point it gets such a high number that it begins generating errors...

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