Please help me fix these shell script errors

Source code:

#!/bin/bash prime_1=0 echo -n "Enter the value of n: " read n echo -n "First $n prime numbers are: " echo -n "2 " counter=1 for((i=3;$counter=2;)) do if [ `expr $i % $j` -ne 0 ] ; then prime_1=1 else prime_1=0 break fi j=`expr $j - 1` done if [ $prime_1 -eq 1 ] ; then echo -n "$i " counter=`expr $counter + 1` fi i=`expr $i + 1`

done echo ""

Error screen:

./prime.sh line 10: (expr $i + 1: syntax error invalid arithmetic operator (error token is "$i+ 1") ./prime . sh: line 20: [: missing ]' ./prime.sh line 10: (expr $i +1: syntax erro invalid arithmetic operator (error token is "$i 1") ./prime . sh: line 20: [: missing ]' ./prime.sh line 10: (expr $i +1: syntax erro invalid arithmetic operator (error token is "$i 1") ./prime . sh: line 20: [: missing ]' ./prime.sh line 10: (expr $i +1: syntax erro invalid arithmetic operator (error token is "$i 1") ./prime . sh: line 20: [: missing ]' ./prime.sh line 10: (expr $i +1: syntax erro invalid arithmetic operator (error token is "$i 1") ./prime . sh: line 20: [: missing ]' ./prime.sh line 10: (expr $i +1: syntax erro invalid arithmetic operator (error token is "$i 1") ./prime . sh: line 20: [: missing ]' ./prime.sh line 10: (expr $i +1: syntax erro invalid arithmetic operator (error token is "$i 1") ./prime . sh: line 20: [: missing ]' ./prime.sh line 10: (expr $i +1: syntax erro invalid arithmetic operator (error token is "$i 1") ./prime . sh: line 20: [: missing ]' ./prime.sh line 10: (expr $i +1: syntax erro invalid arithmetic operator (error token is "$i 1") ./prime . sh: line 20: [: missing ]' ./prime.sh line 10: (expr $i +1: syntax erro invalid arithmetic operator (error token is "$i 1") ./prime . sh: line 20: [: missing ]' ./prime.sh line 10: (expr $i +1: syntax erro invalid arithmetic operator (error token is "$i 1") ./prime . sh: line 20: [: missing ]' ./prime.sh line 10: (expr $i +1: syntax erro invalid arithmetic operator (error token is "$i 1") ./prime . sh: line 20: [: missing ]' ./prime.sh line 10: (expr $i +1: syntax erro invalid arithmetic operator (error token is "$i 1") ./prime . sh: line 20: [: missing ]