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A338441
Lexicographically earliest sequence of distinct squarefree numbers such that for any prime p, any run of consecutive multiples of p has length exactly 3.
3
1, 2, 6, 30, 15, 5, 3, 21, 42, 14, 10, 35, 70, 154, 22, 11, 7, 77, 231, 33, 39, 13, 26, 34, 102, 51, 57, 19, 38, 46, 138, 69, 66, 110, 330, 105, 273, 91, 65, 55, 165, 429, 78, 130, 170, 85, 17, 23, 115, 230, 190, 114, 285, 195, 455, 182, 210, 390, 1365, 1001
OFFSET
1,2
COMMENTS
This sequence is a squarefree variant of A338338.
Conjecture: this is a permutation of the squarefree numbers (A005117).
LINKS
EXAMPLE
The first terms, alongside their prime factors, are:
n a(n) Prime factors
-- ---- -------------
1 1
2 2 2
3 6 2 3
4 30 2 3 5
5 15 3 5
6 5 5
7 3 3
8 21 3 7
9 42 2 3 7
10 14 2 7
11 10 2 5
12 35 5 7
13 70 2 5 7
14 154 2 7 11
15 22 2 11
16 11 11
PROG
(C) // See Links section.
CROSSREFS
KEYWORD
nonn
AUTHOR
Rémy Sigrist, Oct 28 2020
STATUS
approved