
用数组公式:
=IFERROR(INDEX(A:A,SMALL(IF((MID(A$1:A$5,1,1)<>MID(A$1:A$5,2,1))*(MID(A$1:A$5,1,1)<>MID(A$1:A$5,1,3)),ROW($A$1:$A$5)),ROW(A1))),"")

用数组公式:
=IFERROR(INDEX(A:A,SMALL(IF((MID(A$1:A$5,1,1)<>MID(A$1:A$5,2,1))*(MID(A$1:A$5,1,1)<>MID(A$1:A$5,1,3)),ROW($A$1:$A$5)),ROW(A1))),"")