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%I #13 Dec 18 2021 23:37:26
%S 1,2,6,14,3,8,18,38,13,7,4,10,22,46,94,5,12,26,9,20,42,86,29,15,32,11,
%T 24,50,17,36,74,25,52,106,214,43,88,178,358,718,1438,2878,5758,443,37,
%U 19,40,82,166,334,67,34,70,142,286,41,21,44,90,182,61,31,16,51
%N a(1)=1, a(2)=2; for n > 2, a(n) is the least unused positive number k such that j != k and either j | k or k | j, but not both, where j = a(n-1) + 1.
%C Variant of A347113 with the additional restriction that j | k or k | j. - _Michael De Vlieger_, Dec 18 2021.
%H Michael De Vlieger, <a href="/A349681/b349681.txt">Table of n, a(n) for n = 1..10000</a>
%H Michael De Vlieger, <a href="/A349681/a349681.png">Log-log scatterplot of a(n)</a>, for n = 1..2^14, indicating records in red and local minima in blue.
%t j = 3; c[_] = 0; c[2] = 1; {1, 2}~Join~Reap[Do[Set[k, 3]; While[Nand[c[k] == 0, j != k, Xor[Mod[j, k] == 0, Mod[k, j] == 0]], k++]; Sow[k]; Set[c[k], i]; j = k + 1, {i, 3, 64}]][[-1, -1]]
%Y Cf. A347113.
%K nonn
%O 1,2
%A _Michael De Vlieger_, Nov 25 2021
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