Numbers k such that 0 and 2 occur juxtaposed in the base-10 representation of k but not of k-1.

Terms

a(0) =20a(1) =102a(2) =120a(3) =200a(4) =220a(5) =302a(6) =320a(7) =402a(8) =420a(9) =502a(10) =520a(11) =602a(12) =620a(13) =702a(14) =720a(15) =802a(16) =820a(17) =902a(18) =920a(19) =1002a(20) =1020a(21) =1102a(22) =1120a(23) =1200a(24) =1220a(25) =1302a(26) =1320a(27) =1402a(28) =1420a(29) =1502