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%I #16 Jan 07 2025 10:03:47
%S 1,13,17,23,58
%N Lengths of optimal sparse rulers that are not Wichmann rulers.
%C 58 is the last value in the Optimal Ruler Conjecture of Peter Luschny. The conjecture is known to be true to length 213.
%H Peter Luschny, <a href="http://oeis.org/wiki/User:Peter_Luschny/PerfectRulers#The_optimal_ruler_conjecture">Optimal ruler conjecture</a>.
%H Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/SparseRuler.html">Sparse Ruler</a>.
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Sparse_ruler">Sparse ruler</a>.
%e The sparse rulers of length 23 and 58 are as follows:
%e III........I...I..I..I.I
%e II..I.....I.....I.I..I.I
%e IIII.......................I....I...I...I...I...I...I..I..I
%e III...I.I........I........I........I........I..I......I..II
%e III.....I......II.........I.........I.........I..I...I.I..I
%e II.I..I..........I..I......I.......I.........I...I...I...II
%e II.I..I..........I......I..I..........I......I...I...I...II
%e II...I..I...I........I........I........I........I....II.I.I
%Y Cf. A046693, A289761, A308766, A309407, A326499.
%K nonn,hard,more,changed
%O 1,2
%A _Ed Pegg Jr_, Dec 07 2021