Smallest number not occurring earlier fitting the repeating pattern "11223344556677889900".

Terms

a(0) =1a(1) =12a(2) =2a(3) =3a(4) =34a(5) =4a(6) =5a(7) =56a(8) =6a(9) =7a(10) =78a(11) =8a(12) =9a(13) =900a(14) =11a(15) =22a(16) =33a(17) =44a(18) =55a(19) =66a(20) =77a(21) =88a(22) =9900a(23) =112a(24) =23a(25) =344a(26) =556a(27) =67a(28) =788a(29) =99001