JE Number same as GTR-JRNL-BOOK-NBR?

what are you looking for? GTR is the GLTRANSREL file

GL Transaction Conversion
The General Ledger Transaction Interface file contains the information needed
to create transaction within the Lawson General Ledger system when converting
from a non-Lawson system defined in GL65.1 (Transaction Interface
Maintenance).

There is no stated definition aside from data type for the JRNL-BOOK-NBR and no relationship to JE Number

GTR-JBK-SEQ-NBR
The next available journal book IFLR.1 sequence number assigned to an interfaced transaction when added to the Lawson system.

I am looking for the Journal Entry number. I am working with the GLTrans table.

You probably want JE-SEQUENCE. Are you on Lawson 9? using Lawson OLE DB or going directly to your database?

Lawson 9.

The JE number is on the GLCONTROl table and it is called control_group

IS the JE Sequence number to put in sequence a transaction?

as far as i understand, its just an unique number. A surrogate key of sorts (although not specific to the GLTRANS table, that would the the OBJ-ID).