Golf:56 :) 
perl -E'$_=pop;sub r{1..$_,reverse 1..$_-1}say" "x(9-$_),r for r' 9
        1
       121
      12321
     1234321
    123454321
   12345654321
  1234567654321
 123456787654321
12345678987654321
 123456787654321
  1234567654321
   12345654321
    123454321
     1234321
      12321
       121
        1

[download]

Cheers Rolf

In reply to Re^2: Diamonds for fun by LanX
in thread Diamonds for fun by perl_nando

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