A308058 - OEIS

%I #15 Feb 13 2021 14:37:28

%S 1,1,2,1,3,1,4,3,2,2,3,3,4,4,5,1,5,2,4,6,1,7,1,9,5,3,5,4,7,2,5,5,6,2,

%T 6,3,6,4,8,4,9,7,3,7,4,10,1,11,1,13,1,17,1,19,1,22,1,23,1,24,3,8,5,7,

%U 5,8,6,5,9,9,10,2,7,6,7,7,8,7,9,11,2,9,12

%N Lexicographically earliest sequence of positive terms such that for any distinct m and n, a(m) * a(m+1)^2 <> a(n) * a(n+1)^2.

%C This sequence has similarities with A088178; here we consider a(n)*a(n+1)^2, there we consider a(n)*a(n+1).

%H Rémy Sigrist, <a href="/A308058/b308058.txt">Table of n, a(n) for n = 1..10000</a>

%e The first terms, alongside a(n)*a(n+1)^2, are:

%e   n   a(n)  a(n)*a(n+1)^2

%e   --  ----  -------------

%e    1     1              1

%e    2     1              4

%e    3     2              2

%e    4     1              9

%e    5     3              3

%e    6     1             16

%e    7     4             36

%e    8     3             12

%e    9     2              8

%e   10     2             18

%o (PARI) s=0; v=1; for(n=1, 83, print1(v", "); for (w=1, oo, if (!bittest(s,x=v*w^2), s+=2^x; v=w; break)))

%Y See A308057 for an additive variant.

%Y Cf. A088178.

%K nonn

%O 1,3

%A _Rémy Sigrist_, May 10 2019