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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
KEYWORD
nonn,base
AUTHOR
Enrique Navarrete, Jul 27 2019
STATUS
approved

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Last modified March 28 14:38 EDT 2024. Contains 371254 sequences. (Running on oeis4.)