[SunHELP] Korn shell script

if i need to count the number of for loop

for 1 to 10  do {
	i=i+1;
}
echo "$i";

I have headache with 'i=i+1', 
what is it in Korn shell.?
Somewhere i saw use 'let', ((i=$i+1)), ((i++))

Please suggest
Pat.