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A347181 Lexicographically earliest sequence of distinct positive integers such that the first digit of a(n) is visible in a(n) + a(n+1).

%I A347181 #13 Aug 24 2021 14:49:00
%S A347181 1,9,10,2,18,3,20,4,30,5,40,6,50,7,60,8,70,17,14,27,15,16,25,37,26,36,
%T A347181 47,57,28,24,38,35,48,46,58,67,19,12,29,13,68,78,39,34,49,45,59,56,69,
%U A347181 77,80,88,90,79,91,98,11,89,92,87,21,31,22,99,93,66,94,55,95,44,96,23,97,32,41,33,100,42
%N A347181 Lexicographically earliest sequence of distinct positive integers such that the first digit of a(n) is visible in a(n) + a(n+1).
%e A347181 a(1) + a(2) =  1 +  9 = 10;
%e A347181 a(2) + a(3) =  9 + 10 = 19;
%e A347181 a(3) + a(4) = 10 +  2 = 12;
%e A347181 a(4) + a(5) =  2 + 18 = 20;
%e A347181 a(5) + a(6) = 18 +  3 = 21; etc.
%o A347181 (Python)
%o A347181 def aupton(terms):
%o A347181     alst, aset = [1], {1}
%o A347181     while len(alst) < terms:
%o A347181         an, target = 2, str(alst[-1])[0]
%o A347181         while an in aset or target not in str(alst[-1]+an): an += 1
%o A347181         alst.append(an); aset.add(an)
%o A347181     return alst
%o A347181 print(aupton(200)) # _Michael S. Branicky_, Aug 21 2021
%Y A347181 Cf. A347180.
%K A347181 base,nonn
%O A347181 1,2
%A A347181 _Eric Angelini_ and _Carole Dubois_, Aug 21 2021