-l15e'split//,int rand 10**pop;print$a,map{(0..$_-1,$_+1..9)[rand 9]}@_ while++$i%4e4||@_&&($a.=shift@_)'

##</code><code>##

axxxx
axxxx
axxxx
1bxxx
1bxxx
1bxxx
12cxx
12cxx
12cxx
123dx
123dx
123dx
1234e
1234e
1234e
12345
12345

where a != 1, b != 2, c != 3, d != 4, e != 5
      x = can be any digit