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%I #14 Apr 12 2020 13:58:23
%S 1,2,3,5,6,7,10,11,13,14,17,18,20,21,26,27,30,31,37,38,41,43,44,46,50,
%T 52,55,57,58,65,66,70,73,79,82,83,88,91,92,101,102,104,110,111,116,
%U 122,124,127,132,133,141,143,145,146,152,156,157,167,170,171,180
%N Lexicographically earliest sequence of distinct positive integers, which when mapped onto a square spiral, gives a set without four distinct points forming a square.
%C This sequence has similarities with A005282.
%H Rémy Sigrist, <a href="/A333866/b333866.txt">Table of n, a(n) for n = 1..10000</a>
%H Rémy Sigrist, <a href="/A333866/a333866.png">Scatterplot of (A174344(a(n)), A274923(a(n))) in the region -2000 <= x, y <= 2000</a>
%H Rémy Sigrist, <a href="/A333866/a333866.txt">C# program for A333866</a>
%e The first terms, mapped onto a square spiral, are:
%e 65---*---*---*---*---*---*--58--57
%e | |
%e 66 37---*---*---*---*---*--31 *
%e | | | |
%e * 38 17---*---*--14--13 30 55
%e | | | | | |
%e * * 18 5---*---3 * * * <-- As the sequence contains 2, 13
%e | | | | | | | | and 27, it cannot contain 54.
%e * * * 6 1---2 11 * *
%e | | | | | | |
%e 70 41 20 7---*---*--10 27 52
%e | | | | |
%e * * 21---*---*---*---*--26 *
%e | | |
%e * 43--44---*--46---*---*---*--50
%e |
%e 73---*---*---*---*---*--79---*---*
%o (C#) See Links section.
%Y See A333825 for a similar sequences.
%Y Cf. A005282, A174344, A274923.
%K nonn
%O 1,2
%A _Rémy Sigrist_, Apr 08 2020
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