12, 34, 45, 54, 56, 65, 76, 78, 87, 98, 210, 212, 232, 234, 321, 323, 345, 432, 434, 454, 456, 543, 545, 565, 654, 656, 676, 678, 765, 767, 789, 876, 878, 898, 987, 989, 1010, 1012, 1210, 1212, 1232, 2101, 2121, 2123, 2321, 2323, 2343, 3210, 3212, 3232, 3234, 3432, 3434, 3454, 4321, 4323, 4343, 4345, 4543, 4545, 4565, 5432, 5434, 5454, 5456, 5654, 5656, 5676, 5678, 6543, 6545, 6565, 6567, 6765, 6767, 6787, 6789, 7654, 7656, 7676, 7678, 7876, 7878, 7898, 8765, 8767, 8787, 8789, 8987, 8989, 9876, 9878, 9898, 10101, 12121, 21010, 21012, 21210, 21212, 21232, 21234, 23210, 23212, 23232, 23234, 23432, 23434, 23454, 32121, 32123, 32343, 34323, 34545, 34565, 34567, 43210, 43212, 43232, 43234, 43432, 43434, 43454, 45432, 45434, 45454, 45456, 45654, 45656, 45676, 45678, 54321, 54343, 54345, 54543, 54545, 54565, 54567, 56545, 56565, 56765, 56787, 56789, 65432, 65434, 65454, 65456, 65654, 65656, 65676, 65678, 67654, 67656, 67676, 67678, 67876, 67878, 67898, 76565, 76567, 76765, 76767, 76787, 76789, 78765, 78767, 78789, 78987, 87654, 87656, 87676, 87678, 87876, 87878, 87898, 89876, 89878, 89898, 98765, 98767, 98787, 98789, 98987, 98989, 101010, 101012, 101210, 101212, 101232, 101234, 121010, 121012, 121210, 121212, 123210, 123212, 123234, 123432, 123454, 210121, 210123, 212101, 212121, 212343, 232101, 232323, 232345, 234321, 234345, 234543, 234565, 234567, 321010, 321012, 321210, 321212, 321232, 321234, 323210, 323212, 323232, 323234, 323432, 323434, 323454, 343210, 343212, 343232, 343234, 343432, 343434, 343454, 343456, 345432, 345434, 345454, 345456, 345654, 345656, 345676, 345678, 432101, 432123, 432321, 432345, 434321, 434343, 434543, 434545, 434565, 454321, 454323, 454343, 454345, 454545, 454565, 454567, 456543, 456565, 456567, 456765, 456787, 456789, 543210, 543212, 543234, 543432, 543434, 543454, 543456, 545432, 545434, 545454, 545456, 545654, 545656, 545676, 545678, 565432, 565434, 565454.

9876543, 9876545, 9876565, 9876567, 9876765, 9876767, 9876787, 9876789, 9878765, 9878767, 9878787, 9878789, 9878987, 9878989, 9898765, 9898767, 9898787, 9898789, 9898987, 9898989.