The 13 is probably the numeric value of one of the following in this list:
Pl> USER_STRING_ALIASUser's alias or real name on real name based BBSs
Pl> USER_STRING_REALNAMEUser's real name or company name
Pl> USER_STRING_HANDLEUser's chat handle
Pl> USER_STRING_COMPUTERUser's computer type description
Pl> USER_STRING_NOTEUser's note/Caller-ID
Pl> USER_STRING_ADDRESSUser's street address
Pl> USER_STRING_LOCATIONUser's city, state
Pl> USER_STRING_ZIPCODEUser's zip/postal code
Pl> USER_STRING_PASSWORDUser's password
Pl> USER_STRING_BIRTHDAYUser's birthday (MM/DD/YY or DD/MM/YY)
Pl> USER_STRING_PHONEUser's phone number
Pl> USER_STRING_MODEMUser's modem type description
Pl> USER_STRING_COMMENT
Nightfox
---
� Synchronet � Digital Distortion: digitaldistortionbbs.com