A. ff permutations

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feffff fffeff fffffe fffefe fefffe fefeff
eeffff ffeeff ffffee ffeeee eeffee eeeeff
ddffff ffddff ffffdd ffdddd ddffdd ddddff
ccffff ffccff ffffcc ffcccc ccffcc ccccff
bbffff ffbbff ffffbb ffbbbb bbffbb bbbbff
aaffff ffaaff ffffaa ffaaaa aaffaa aaaaff
99ffff ff99ff ffff99 ff9999 99ff99 9999ff
88ffff ff88ff ffff88 ff8888 88ff88 8888ff
77ffff ff77ff ffff77 ff7777 77ff77 7777ff
66ffff ff66ff ffff66 ff6666 66ff66 6666ff
55ffff ff55ff ffff55 ff5555 55ff55 5555ff
44ffff ff44ff ffff44 ff4444 44ff44 4444ff
33ffff ff33ff ffff33 ff3333 33ff33 3333ff
22ffff ff22ff ffff22 ff2222 22ff22 2222ff
11ffff ff11ff ffff11 ff1111 11ff11 1111ff
00ffff ff00ff ffff00 ff0000 00ff00 0000ff

B. ee permutations

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eeffff ffeeff ffffee ffeeee eeffee eeeeff
eeeeee eeeeee eeeeee eeeeee eeeeee eeeeee
ddeeee eeddee eeeedd eedddd ddeedd ddddee
cceeee eeccee eeeecc eecccc cceecc ccccee
bbeeee eebbee eeeebb eebbbb bbeebb bbbbee
aaeeee eeaaee eeeeaa eeaaaa aaeeaa aaaaee
99eeee ee99ee eeee99 ee9999 99ee99 9999ee
88eeee ee88ee eeee88 ee8888 88ee88 8888ee
77eeee ee77ee eeee77 ee7777 77ee77 7777ee
66eeee ee66ee eeee66 ee6666 66ee66 6666ee
55eeee ee55ee eeee55 ee5555 55ee55 5555ee
44eeee ee44ee eeee44 ee4444 44ee44 4444ee
33eeee ee33ee eeee33 ee3333 33ee33 3333ee
22eeee ee22ee eeee22 ee2222 22ee22 2222ee
11eeee ee11ee eeee11 ee1111 11ee11 1111ee
00eeee ee00ee eeee00 ee0000 00ee00 0000ee

C. ee & ff permutations

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ffeeff eeffff ffffee eeffff ffffee ffeeff
eeeeff eeeeff eeffee eeffee ffeeee ffeeee
ddeeff eeddff ddffee eeffdd ffddee ffeedd
cceeff eeccff ccffee eeffcc ffccee ffeecc
bbeeff eebbff bbffee eeffbb ffbbee ffeebb
aaeeff eeaaff aaffee eeffaa ffaaee ffeeaa
99eeff ee99ff 99ffee eeff99 ff99ee ffee99
88eeff ee88ff 88ffee eeff88 ff88ee ffee88
77eeff ee77ff 77ffee eeff77 ff77ee ffee77
88eeff ee88ff 88ffee eeff88 ff88ee ffee88
77eeff ee77ff 77ffee eeff77 ff77ee ffee77
66eeff ee66ff 66ffee eeff66 ff66ee ffee66
55eeff ee55ff 55ffee eeff55 ff55ee ffee55
44eeff ee44ff 44ffee eeff44 ff44ee ffee44
33eeff ee33ff 33ffee eeff33 ff33ee ffee33
22eeff ee22ff 22ffee eeff22 ff22ee ffee22
11eeff ee11ff 11ffee eeff11 ff11ee ffee11
00eeff ee00ff 00ffee eeff00 ff00ee ffee00
ccddff ddccff ccffdd ddffcc ffccdd ffddcc
ccddee ddccee cceedd ddeecc eeccdd eeddcc
bbddee ddbbee bbeedd ddeebb eebbdd eeddbb
1188ff 11ff88 8811ff 88ff11 ff1188 ff8811
1188cc 11cc88 8811cc 88cc11 cc1188 cc8811
118811 111188 881111 881111 111188 118811

E. dd & ff permutations

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ffddff ddffff ffffdd ddffff ffffdd ffddff
eeddff ddeeff eeffdd ddffee ffeedd ffddee
ddddff ddddff ddffdd ddffdd ffdddd ffdddd
ccddff ddccff ccffdd ddffcc ffccdd ffddcc
bbddff ddbbff bbffdd ddffbb ffbbdd ffddbb
aaddff ddaaff aaffdd ddffaa ffaadd ffddaa
99ddff dd99ff 99ffdd ddff99 ff99dd ffdd99
88ddff dd88ff 88ffdd ddff88 ff88dd ffdd88
77ddff dd77ff 77ffdd ddff77 ff77dd ffdd77
66ddff dd66ff 66ffdd ddff66 ff66dd ffdd66
55ddff dd55ff 55ffdd ddff55 ff55dd ffdd55
44ddff dd44ff 44ffdd ddff44 ff44dd ffdd44
33ddff dd33ff 33ffdd ddff33 ff33dd ffdd33
22ddff dd22ff 22ffdd ddff22 ff22dd ffdd22
11ddff dd11ff 11ffdd ddff11 ff11dd ffdd11
00ddff dd00ff 00ffdd ddff00 ff00dd ffdd00
ccddff ddccff ccffdd ddffcc ffccdd ffddcc
ccdddd ddccdd ccdddd ddddcc ddccdd ddddcc
bbdddd ddbbdd bbdddd ddddbb ddbbdd ddddbb