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 A309390 Set a(1)=10. Thereafter a(n) is the smallest positive number not yet in the sequence that contains exactly one even digit and one odd digit from a(n-1). 1
 10, 100, 101, 102, 12, 21, 112, 120, 103, 30, 130, 104, 14, 41, 114, 124, 121, 122, 123, 23, 32, 132, 125, 25, 52, 152, 126, 16, 61, 106, 105, 50, 150, 107, 70, 170, 108, 18, 81, 118, 128, 127, 27, 72, 172, 129, 29, 92, 192, 142, 134, 34, 43, 143, 140, 109, 90, 190, 110, 160, 116 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Numbers such as 3, 8, 20, 31, and 42 are not in the sequence since by definition all terms must contain both odd and even digits. LINKS EXAMPLE a(2)=100 since it is the smallest number not yet in the sequence that contains an even digit (0) and an odd digit (1) from a(1)=10. a(7)=112 since it is the smallest number not yet in the sequence that contains an even digit (2) and an odd digit (1) from a(6)=21. a(27)=126 is not 105 since 105 would contain two odd digits (1 and 5) from a(26)=152. CROSSREFS Cf. A318700 (positive numbers that contain both odd and even digits). Sequence in context: A266798 A268449 A289826 * A341692 A323708 A293870 Adjacent sequences:  A309387 A309388 A309389 * A309391 A309392 A309393 KEYWORD nonn,base AUTHOR Enrique Navarrete, Jul 27 2019 STATUS approved

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Last modified April 17 18:52 EDT 2021. Contains 343070 sequences. (Running on oeis4.)