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%I A349978 #12 Dec 09 2021 02:44:14
%S A349978 1,13,17,23,58
%N A349978 Lengths of optimal sparse rulers that are not Wichmann rulers.
%C A349978 58 is the last value in the Optimal Ruler Conjecture of Peter Luschny. The conjecture is known to be true to length 213.
%H A349978 Peter Luschny, <a href="http://oeis.org/wiki/User:Peter_Luschny/PerfectRulers#The_optimal_ruler_conjecture">Optimal ruler conjecture</a>.
%H A349978 Wikipedia, <a href="https://en.wikipedia.org/wiki/Sparse_ruler">Sparse ruler</a>.
%e A349978 The sparse rulers of length 23 and 58 are as follows:
%e A349978 III........I...I..I..I.I
%e A349978 II..I.....I.....I.I..I.I
%e A349978 IIII.......................I....I...I...I...I...I...I..I..I
%e A349978 III...I.I........I........I........I........I..I......I..II
%e A349978 III.....I......II.........I.........I.........I..I...I.I..I
%e A349978 II.I..I..........I..I......I.......I.........I...I...I...II
%e A349978 II.I..I..........I......I..I..........I......I...I...I...II
%e A349978 II...I..I...I........I........I........I........I....II.I.I
%Y A349978 Cf. A046693, A289761, A308766, A309407, A326499.
%K A349978 nonn,hard,more
%O A349978 1,2
%A A349978 _Ed Pegg Jr_, Dec 07 2021

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