Quick script to generate a list of random IP addresses via nmap.

randymarsh.sh

#!/usr/bin/env bash

dir="/tmp/$0"
mkdir -p "$dir"

nmap -n -sL -iR "$1" |
sed '1,2d;$d' |
awk '{print$5}' |
sort -t. -k1,1n -k2,2n -k3,3n -k4,4n |
tee "$dir/$(date +%s)"

########################################

#!/usr/bin/env bash

dir="/tmp/$0"
mkdir -p "$dir"

nmap -n -sL -iR "$1" \
|sed '1,2d;$d' \
|awk '{print$5}' \
|sort -t. -k1,1n -k2,2n -k3,3n -k4,4n \
|tee "$dir/$(date +%s)"

########################################

#!/usr/bin/env bash

dir="/tmp/$0"
mkdir -p "$dir"

nmap -n -sL -iR "$1" | sed '1,2d;$d' | awk '{print$5}' | sort -t. -k1,1n -k2,2n -k3,3n -k4,4n | tee "$dir/$(date +%s)"

Couldn't decide which was the appropriate style. So here's all three.