There's an interesting number pattern: 
1
1 1
2 1
1 2 1 1
1 1 1 2 2 1
3 1 2 2 1 1

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For those of you that don't know this pattern, each line is a description of the previous line. For instance, the line "1 1 1 2 2 1" describes the line "1 2 1 1", because it says "one 1, one 2, two 1's". And so on.

On PerlGuru.com, there was recently a quiz to come up with a good (fast? short?) way to create these lines in Perl. I came up with a very short solution, as well as a very fast solution. These are in the form: 
@a = (1);
for (1..10) {
  print "@a\n";
  # real juicy stuff here
}

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I'd like to see possible solutions from people. My fastest code executed the 1..10 loop 500 times in 2.40 seconds, and a 1..35 loop 10 times in 43.51 seconds. My shortest one is a bit slower, because it uses a regex, at 3.76 seconds and 57.35 seconds.

In reply to Generating a Pattern by japhy

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