Help with sh script loop counting

[Brake Fail]

This is mainly using scripts using bash as interpreter and as a result of using the at command I have to meter sh. But I can not so I ask for your help.

This is my bash script that works well:

#!/bin/bash 

a=0

while [ $a -ne 10 ]
do 
echo $a >>/dev/pts/0
(( a = a +1 ))
done 
exit 0

It therefore gives 0,1,2,3,4,5,6,7,8 and 9.

and I would do the same thing in sh unfortunately it does not:

(( a = a + 1 ))

So if someone knows an equivalent in sh

[Praetor]

Already, for my part, for bash, I use:

a = $(( a + 1 ))
(or a=$(( $a + 1 )) I know more)

testing to see


EDIT, I do not know if both operate bash shell
REED: it works on this test:

 #!/bin/sh 
 # 

  i=0 
  while true, do i=$(( $i + 1)) ; echo $i ; done

[MindSpace]

#!bin/sh
for((a=0;a<=10;a++)
do 
echo ${a}>/dev/pts/0
done

OR

#!bin/sh
for a in $(seq 0 1 10)
do 
echo ${a}>/dev/pts/0
done

finally ... there's lots of solutions

[Brake Fail]

That was the exact answer to my question.
Thank you for the quick responses.