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%I #23 Apr 09 2023 10:54:37
%S 1,2,4,3,5,6,7,8,9,20,10,11,30,22,13,12,14,15,16,24,17,23,18,25,19,21,
%T 26,28,27,29,31,32,40,33,41,35,34,37,36,42,39,43,44,45,46,38,50,47,48,
%U 60,49,52,53,62,63,64,54,55,56,57,58,66,59,67,70,65,68,69,80,72,73,76,75,74,77,78
%N a(1) = 1, a(2) = 2; for n > 2, a(n) is the least positive integer not occurring earlier such that a(n) shares no digit with a(n-2) + a(n-1).
%C The sequence is likely to be finite although it contains at least 100000 terms.
%C Sequence is finite with 4128755 terms, since a(4128754) = 46946449 and a(4128755) = 777000707 have sum 823947156. - _Michael S. Branicky_, Apr 08 2023
%H Michael S. Branicky, <a href="/A362075/b362075.txt">Table of n, a(n) for n = 1..10000</a>
%H Michael S. Branicky, <a href="/A362075/a362075_1.py.txt">Python program</a>
%H Scott R. Shannon, <a href="/A362075/a362075.png">Image of the first 100000 terms</a>. The green line is a(n) = n.
%e a(10) = 20 as a(8) + a(9) = 8 + 9 = 17, and 20 is the smallest unused number that does not contain the digits 1 or 7.
%o (Python) # see linked program that generates the full sequence
%Y Cf. A362076, A342441, A342442, A067581, A297065.
%K nonn,base,fini
%O 1,2
%A _Scott R. Shannon_, Apr 08 2023