#!/usr/bin/perl -w
use strict;

while (<DATA>) {
    $_ =~ tr/!@#$%^&*//d;  # will you encounter funky chars?
    next unless ($_ =~/(^\d+)/);
    print $_;
}

__DATA__
START 
1 
2 
3! 
4
5
END

START
1*
2
3
4
5
6
END
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