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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A382376 Lexicographically earliest sequence of distinct positive integers such that the number of distinct prime factors of adjacent terms differ exactly by one.

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%I A382376 #12 Mar 26 2025 17:49:13
%S A382376 1,2,6,3,10,4,12,5,14,7,15,8,18,9,20,11,21,13,22,16,24,17,26,19,28,23,
%T A382376 33,25,34,27,35,29,36,30,38,31,39,32,40,37,44,41,45,42,46,43,48,47,50,
%U A382376 49,51,53,52,59,54,60,55,61,56,64,57,66,58,67,62,70,63
%N A382376 Lexicographically earliest sequence of distinct positive integers such that the number of distinct prime factors of adjacent terms differ exactly by one.
%C A382376 All primorial numbers appear in the sequence (we can use similar arguments as for A382357).
%C A382376 Conjecture: this sequence is a permutation of the positive integers.
%H A382376 Rémy Sigrist, <a href="/A382376/b382376.txt">Table of n, a(n) for n = 1..10000</a>
%H A382376 Rémy Sigrist, <a href="/A382376/a382376.gp.txt">PARI program</a>
%e A382376 The initial terms are:
%e A382376   n   a(n)  A001221(a(n))
%e A382376   --  ----  -------------
%e A382376    1     1              0
%e A382376    2     2              1
%e A382376    3     6              2
%e A382376    4     3              1
%e A382376    5    10              2
%e A382376    6     4              1
%e A382376    7    12              2
%e A382376    8     5              1
%e A382376    9    14              2
%e A382376   10     7              1
%e A382376   11    15              2
%e A382376   12     8              1
%e A382376   13    18              2
%e A382376   14     9              1
%e A382376   15    20              2
%o A382376 (PARI) \\ See Links section.
%Y A382376 Cf. A001221, A382357, A382374, A382377.
%K A382376 nonn
%O A382376 1,2
%A A382376 _Rémy Sigrist_, Mar 23 2025