alpha.chen / gmail.com wrote:
> A short but hopefully sweet solution:
> 
> [...]

Sweet indeed, i like especialy the to_i(2), didn't thought about that.
But running your solution with rule 145 gave me

X
  X
XX  X
   X  X
XXX  X  X
  X X  X  X
XX    X  X  X
   XXX  X  X  X
XXX  X X  X  X  X
  X X    X  X  X  X
XX    XXX  X  X  X  X
   XXX  X X  X  X  X  X
XXX  X X    X  X  X  X  X
  X X    XXX  X  X  X  X  X
XX    XXX  X X  X  X  X  X  X
   XXX  X X    X  X  X  X  X  X
XXX  X X    XXX  X  X  X  X  X  X
  X X    XXX  X X  X  X  X  X  X  X
XX    XXX  X X    X  X  X  X  X  X  X
   XXX  X X    XXX  X  X  X  X  X  X  X

While my solution produced

 0:                    X
 1:XXXXXXXXXXXXXXXXXXX  XXXXXXXXXXXXXXXXXXXX
 2:XXXXXXXXXXXXXXXXXX X  XXXXXXXXXXXXXXXXXXX
 3:XXXXXXXXXXXXXXXXX   X  XXXXXXXXXXXXXXXXXX
 4:XXXXXXXXXXXXXXXX XX  X  XXXXXXXXXXXXXXXXX
 5:XXXXXXXXXXXXXXX    X  X  XXXXXXXXXXXXXXXX
 6:XXXXXXXXXXXXXX XXX  X  X  XXXXXXXXXXXXXXX
 7:XXXXXXXXXXXXX   X X  X  X  XXXXXXXXXXXXXX
 8:XXXXXXXXXXXX XX    X  X  X  XXXXXXXXXXXXX
 9:XXXXXXXXXXX    XXX  X  X  X  XXXXXXXXXXXX
10:XXXXXXXXXX XXX  X X  X  X  X  XXXXXXXXXXX
11:XXXXXXXXX   X X    X  X  X  X  XXXXXXXXXX
12:XXXXXXXX XX    XXX  X  X  X  X  XXXXXXXXX
13:XXXXXXX    XXX  X X  X  X  X  X  XXXXXXXX
14:XXXXXX XXX  X X    X  X  X  X  X  XXXXXXX
15:XXXXX   X X    XXX  X  X  X  X  X  XXXXXX
16:XXXX XX    XXX  X X  X  X  X  X  X  XXXXX
17:XXX    XXX  X X    X  X  X  X  X  X  XXXX
18:XX XXX  X X    XXX  X  X  X  X  X  X  XXX
19:X   X X    XXX  X X  X  X  X  X  X  X  XX
20: XX    XXX  X X    X  X  X  X  X  X  X  X


Anyone who can confirm one of these as 'correct' ?

cheers

Simon