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A034298 a(n) = min_S max_i b_i where S={b_i} (1 <= i <= n), b_i > 0, b_i distinct and either b_i|b_{i-1} or b_{i-1}|b_i.

%I A034298 #32 Aug 03 2022 15:30:07
%S A034298 1,2,3,4,6,6,8,9,10,12,12,14,15,16,18,18,20,21,22,24,24,26,27,28,30,
%T A034298 30,32,33,35,36,39,40,42,42,44,44,45,48,48,50,50,51,52,54,55,56,57,60,
%U A034298 60,63,64,66,66,68,69,70,70,72,75,76,77,78,78,80,81,84,87,88
%N A034298 a(n) = min_S max_i b_i where S={b_i} (1 <= i <= n), b_i > 0, b_i distinct and either b_i|b_{i-1} or b_{i-1}|b_i.
%H A034298 E. J. Friedman, <a href="https://erich-friedman.github.io/mathmagic/1198.html">Problem of the Month (November 1998)</a>, Math. Magic.
%e A034298 For example, a(12)=14 because of {9, 3, 6, 12, 4, 8, 2, 10, 5, 1, 7, 14} and the fact that no sequence of 12 distinct positive integers < 14 has this division property.
%e A034298 a(32) = 40 because of {22, 11, 33, 3, 39, 13, 26, 2, 34, 17, 1, 10, 20, 40, 8, 16, 32, 4, 28, 14, 7, 35, 5, 15, 30, 6, 24, 12, 36, 18, 9, 27};
%e A034298 a(34) = 42 because of {22, 11, 33, 3, 39, 13, 26, 2, 34, 17, 1, 10, 20, 40, 8, 16, 32, 4, 28, 14, 42, 21, 7, 35, 5, 15, 30, 6, 24, 12, 36, 18, 9, 27};
%e A034298 a(37) = 45 because of {17, 34, 2, 38, 19, 1, 26, 13, 39, 3, 33, 11, 22, 44, 4, 16, 32, 8, 24, 6, 12, 36, 18, 9, 45, 15, 30, 10, 20, 40, 5, 35, 7, 21, 42, 14, 28}.
%Y A034298 Cf. A035280, A337125.
%K A034298 nonn,nice
%O A034298 1,2
%A A034298 _Erich Friedman_
%E A034298 a(31)-a(37) from _Xavier Martres_, Apr 26 2019
%E A034298 More terms from _Jinyuan Wang_, Aug 02 2022