[UNIX] seq (in Linux) equivalent

#
# Bourne shell functions similar to 'seq' in linux, except without step
# you can use it to do this in a for loop
# for i in `range 1 100`
# do
#    do-something
# done
#
range1()
{
 start=$1
 end=$2
 count=$start
 rc=""
 while [ $count -le $end ]
 do
  rc="$rc $count"
  count=`expr $count + 1`
 done
 echo $rc
}
range2()
{
 perl -e "\$,=\" \"; print $1..$2;"
}
range3()
{
 gawk -v s=$1 -v e=$2 'END{for(i=s;i<=e;++i) {printf("%d ",i)}}' /dev/null
}
range4()
{
 echo "for {set i $1} {\$i<=$2} {incr i} {puts -nonewline \"\$i \"}" | tclsh
}
range5()
{
 yes | pr -f -n | head -`expr $2 + 3` | tail -`expr $2 - $1 + 1` | cut -c1-5
}