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%I #9 Oct 29 2020 02:41:58
%S 1,2,6,3,5,10,14,7,11,22,26,13,15,30,34,17,19,38,42,21,23,46,58,29,31,
%T 62,66,33,35,70,74,37,39,78,82,41,43,86,94,47,51,102,106,53,55,110,
%U 114,57,59,118,122,61,65,130,134,67,69,138,142,71,73,146,154,77
%N Lexicographically earliest sequence of distinct squarefree numbers such that for any prime p, any run of consecutive multiples of p has length exactly 2.
%C This sequence is a squarefree variant of A280864.
%C Conjecture: this sequence is a permutation of the squarefree numbers (A005117).
%H Rémy Sigrist, <a href="/A338444/b338444.txt">Table of n, a(n) for n = 1..10000</a>
%H Rémy Sigrist, <a href="/A338444/a338444.txt">C program for A338444</a>
%e The first terms, alongside their prime factors, are:
%e n a(n) Prime factors
%e -- ---- -------------
%e 1 1
%e 2 2 2
%e 3 6 2 3
%e 4 3 3
%e 5 5 5
%e 6 10 2 5
%e 7 14 2 7
%e 8 7 7
%e 9 11 11
%e 10 22 2 11
%e 11 26 2 13
%e 12 13 13
%e 13 15 3 5
%e 14 30 2 3 5
%e 15 34 2 17
%e 16 17 17
%o (C) See Links section.
%Y Cf. A005117, A280864, A338441.
%K nonn
%O 1,2
%A _Rémy Sigrist_, Oct 28 2020
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