This information is stored in the packed descriptor, db2cat can be used to dump this info. The command is:
db2cat -d <db name> -n <table name> -s <schema name> -o <output file>
Example:
db2cat -d sample -n employee -s test -o db2cat.out
test@panipuri /home/test > grep -i build db2cat.out
Log Index Build : OFF