cat command.sh 
#!/bin/bash
for ((i=3;i<20;i++))
do 
echo rule $i deny ip source 10.0.16.2 0 destination 10.0.16.$((i+10)) 0
done>>/root/script/apple.txt

cat apple.txt
rule 3 deny ip source 10.0.16.2 0 destination 10.0.16.13 0
rule 4 deny ip source 10.0.16.2 0 destination 10.0.16.14 0
rule 5 deny ip source 10.0.16.2 0 destination 10.0.16.15 0
rule 6 deny ip source 10.0.16.2 0 destination 10.0.16.16 0
rule 7 deny ip source 10.0.16.2 0 destination 10.0.16.17 0
rule 8 deny ip source 10.0.16.2 0 destination 10.0.16.18 0
rule 9 deny ip source 10.0.16.2 0 destination 10.0.16.19 0
rule 10 deny ip source 10.0.16.2 0 destination 10.0.16.20 0
rule 11 deny ip source 10.0.16.2 0 destination 10.0.16.21 0
rule 12 deny ip source 10.0.16.2 0 destination 10.0.16.22 0
rule 13 deny ip source 10.0.16.2 0 destination 10.0.16.23 0
rule 14 deny ip source 10.0.16.2 0 destination 10.0.16.24 0
rule 15 deny ip source 10.0.16.2 0 destination 10.0.16.25 0
rule 16 deny ip source 10.0.16.2 0 destination 10.0.16.26 0
rule 17 deny ip source 10.0.16.2 0 destination 10.0.16.27 0
rule 18 deny ip source 10.0.16.2 0 destination 10.0.16.28 0
rule 19 deny ip source 10.0.16.2 0 destination 10.0.16.29 0