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A375306 Terms as well as digits fit the even/odd/odd pattern; this is the lexicographically earliest injective sequence with this property.

%I A375306 #16 Aug 12 2024 13:18:38
%S A375306 0,1,3,2,5,7,4,9,101,10,11,21,12,13,23,14,15,25,16,17,27,18,19,29,30,
%T A375306 31,41,32,33,43,34,35,45,36,37,47,38,39,49,50,51,61,52,53,63,54,55,65,
%U A375306 56,57,67,58,59,69,70,71,81,72,73,83,74,75,85,76,77,87,78,79,89,90,91,211,6,93,213,8,95,215,2110,97
%N A375306 Terms as well as digits fit the even/odd/odd pattern; this is the lexicographically earliest injective sequence with this property.
%H A375306 Michael S. Branicky, <a href="/A375306/b375306.txt">Table of n, a(n) for n = 1..10000</a>
%e A375306 a(7) = 4, a(8) = 9, a(9) = 101, a(10) = 10; terms follow the even/odd/odd pattern and so do their digits: 4/9/1 and 0/1/1.
%o A375306 (Python)
%o A375306 from itertools import count, islice, repeat
%o A375306 def c(s, i):
%o A375306     return all(int(d)%2 == int((i+j)%3 > 0) for j, d in enumerate(s))
%o A375306 def agen(): # generator of terms
%o A375306     seen, s = set(), 0
%o A375306     for n in count(0):
%o A375306         eo = int(n%3 > 0)
%o A375306         an = next(k for k in count(eo, 2) if k not in seen and c(str(k), s))
%o A375306         yield an
%o A375306         seen.add(an)
%o A375306         s += len(str(an))
%o A375306 print(list(islice(agen(), 99))) # _Michael S. Branicky_, Aug 11 2024
%Y A375306 Cf. A217555, A375305.
%K A375306 base,nonn
%O A375306 1,3
%A A375306 _Eric Angelini_, Aug 11 2024