Fix a PHP script

I have a PHP loop that sends an email to a list of subscribers. The script actually works fine (it sends the emails, all is good). However, I get the PHP Warnings seen at the bottom of this message. I'm hoping someone can resolve the issue by telling me what code to change. Please post your bid for instructions. Thanks! =============================== THE PART OF SCRIPT CAUSING ISSUES: =============================== for($x=1;$x<=$i;$x++) { if($x>1 AND (${'email' . $x}<>$lastloopemail)) { // This is line 135 ${'mail' . $x-1} = new PHPMailer; ${'mail' . $x-1}->setFrom($fromemailask, '[login to view URL]'); ${'mail' . $x-1}->DKIM_domain = '[login to view URL]'; ${'mail' . $x-1}->DKIM_private = '/var/[login to view URL]'; ${'mail' . $x-1}->DKIM_selector = '[login to view URL]'; ${'mail' . $x-1}->DKIM_passphrase = ''; ${'mail' . $x-1}->DKIM_identity = ${'mail' . $x-1}->From; ${'mail' . $x-1}->addAddress($lastloopemail); ${'mail' . $x-1}->addBCC($toemailadmin); ${'mail' . $x-1}->isHTML(true); ${'mail' . $x-1}->Subject = $subject; ${'mail' . $x-1}->Body = $message; ${'mail' . $x-1}->XMailer = ' '; // Removes the php X-Mailer header if(!${'mail' . $x-1}->send()) { // This is line 149 echo 'Mailer Error: ' . ${'mail' . $x}->ErrorInfo; } else { echo 'Message has been sent'; }} ============================= THE ERRORS I GET ON EVERY LOOP: ============================= PHP Warning: A non-numeric value encountered in /var/www/[login to view URL] on line 136 PHP Warning: A non-numeric value encountered in /var/www/[login to view URL] on line 137 PHP Warning: A non-numeric value encountered in /var/www/[login to view URL] on line 138 PHP Warning: A non-numeric value encountered in /var/www/[login to view URL] on line 139 PHP Warning: A non-numeric value encountered in /var/www/[login to view URL] on line 140 PHP Warning: A non-numeric value encountered in /var/www/[login to view URL] on line 141 PHP Warning: A non-numeric value encountered in /var/www/[login to view URL] on line 142 PHP Warning: A non-numeric value encountered in /var/www/[login to view URL] on line 142 PHP Warning: A non-numeric value encountered in /var/www/[login to view URL] on line 143 PHP Warning: A non-numeric value encountered in /var/www/[login to view URL] on line 144 PHP Warning: A non-numeric value encountered in /var/www/[login to view URL] on line 145 PHP Warning: A non-numeric value encountered in /var/www/[login to view URL] on line 146 PHP Warning: A non-numeric value encountered in /var/www/[login to view URL] on line 147 PHP Warning: A non-numeric value encountered in /var/www/[login to view URL] on line 148 PHP Warning: A non-numeric value encountered in /var/www/[login to view URL] on line 149