Group 0 (1 unique chains):

x1 = 000000001111111 [0000000011111111]
x2 = 000011110000111 [0000111100001111]
x3 = 001100110011001 [0011001100110011]
x4 = 010101010101010 [0101010101010101]
x5 = x2 & x3 = 000000110000001 [0000001100000011]
x6 = x1 | x5 = 000000111111111 [0000001111111111]
x7 = x3 ^ x6 = 001100001100110 [0011000011001100]
x8 = x4 ^ x6 = 010101101010101 [0101011010101010]
x9 = x4 | x7 = 011101011101110 [0111010111011101]
x10 = x2 ^ x8 = 010110011010010 [0101100110100101]
x11 = x5 | x9 = 011101111101111 [0111011111011111]
x12 = x7 < x10 = 010010010010000 [0100100100100001] = ~d
x13 = x2 ^ x11 = 011110001101000 [0111100011010000]
x14 = x11 ^ x12 = 001111101111111 [0011111011111110] = g
x15 = x1 ^ x13 = 011110000010111 [0111100000101111]
x16 = x7 ^ x13 = 010010000001110 [0100100000011100] = ~a
x17 = x9 & x15 = 011100000000110 [0111000000001101] = ~f
x18 = x10 < x15 = 001000000000101 [0010000000001010] = ~c
x19 = x8 | x16 = 010111101011111 [0101111010111110]
x20 = x6 ^ x19 = 010111010100000 [0101110101000001] = ~e
x21 = x10 < x19 = 000001100001101 [0000011000011010] = ~b

  0   1   2   3   4   5   6   7   8   9  10  11  12  13  14  15 
  _       _   _       _   _   _   _   _   _               _   _ 
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