A378106 - OEIS

%I #7 Nov 17 2024 13:07:40

%S 1,2,4,8,16,3,6,12,24,48,96,9,18,36,72,7,14,28,56,5,10,20,40,80,160,

%T 15,30,60,120,240,480,32,64,128,256,25,50,100,200,400,800,1600,75,150,

%U 300,600,1200,2400,4800,192,19,38,76,152,13,26,52,104,208,416,41

%N Lexicographically earliest sequence of distinct positive integers such that among two consecutive terms, the least term divides a positive number whose decimal expansion appears in that of the other term.

%C Will every integer appear in the sequence?

%H Rémy Sigrist, <a href="/A378106/b378106.txt">Table of n, a(n) for n = 1..10000</a>

%H Rémy Sigrist, <a href="/A378106/a378106.gp.txt">PARI program</a>

%e The first terms are:

%e   n   a(n)

%e   --  ----

%e    1     1

%e    2     2

%e    3     4

%e    4     8

%e    5    16

%e    6     3      (3 divides 6, and 6 appears in 16)

%e    7     6

%e    8    12

%e    9    24

%e   10    48

%e   11    96

%e   12     9

%e   13    18

%e   14    36

%e   15    72

%o (PARI) \\ See Links section.

%Y See A342072 and A378107 for similar sequences.

%K nonn,base

%O 1,2

%A _Rémy Sigrist_, Nov 16 2024