Numbers with exactly four distinct base-10 digits.

Terms

a(0) =1023a(1) =1024a(2) =1025a(3) =1026a(4) =1027a(5) =1028a(6) =1029a(7) =1032a(8) =1034a(9) =1035a(10) =1036a(11) =1037a(12) =1038a(13) =1039a(14) =1042a(15) =1043a(16) =1045a(17) =1046a(18) =1047a(19) =1048a(20) =1049a(21) =1052a(22) =1053a(23) =1054a(24) =1056a(25) =1057a(26) =1058a(27) =1059a(28) =1062a(29) =1063