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%I #10 Oct 29 2020 02:42:02
%S 1,2,6,30,15,5,3,21,42,14,10,35,70,154,22,11,7,77,231,33,39,13,26,34,
%T 102,51,57,19,38,46,138,69,66,110,330,105,273,91,65,55,165,429,78,130,
%U 170,85,17,23,115,230,190,114,285,195,455,182,210,390,1365,1001
%N Lexicographically earliest sequence of distinct squarefree numbers such that for any prime p, any run of consecutive multiples of p has length exactly 3.
%C This sequence is a squarefree variant of A338338.
%C Conjecture: this is a permutation of the squarefree numbers (A005117).
%H Rémy Sigrist, <a href="/A338441/b338441.txt">Table of n, a(n) for n = 1..10000</a>
%H Rémy Sigrist, <a href="/A338441/a338441.txt">C program for A338441</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 30 2 3 5
%e 5 15 3 5
%e 6 5 5
%e 7 3 3
%e 8 21 3 7
%e 9 42 2 3 7
%e 10 14 2 7
%e 11 10 2 5
%e 12 35 5 7
%e 13 70 2 5 7
%e 14 154 2 7 11
%e 15 22 2 11
%e 16 11 11
%o (C) See Links section.
%Y Cf. A005117, A338338, A338444.
%K nonn
%O 1,2
%A _Rémy Sigrist_, Oct 28 2020
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