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A348485 Lexicographically earliest sequence of positive integers in which, for all positive k, there are exactly k contiguous pairs whose product is k, and a(k) * a(k+1) <> a(k+1) * a(k+2).

%I A348485 #10 Oct 25 2021 11:05:53
%S A348485 1,1,2,2,1,3,2,2,3,1,4,2,2,3,1,5,2,3,3,2,4,3,2,4,3,3,4,2,5,1,7,2,4,3,
%T A348485 3,4,2,5,1,7,2,4,3,3,4,2,5,1,7,2,5,1,7,2,5,3,3,4,4,3,3,4,4,3,3,4,4,5,
%U A348485 2,7,1,9,2,5,3,3,5,2,7,1,10,2,7,1,11,2
%N A348485 Lexicographically earliest sequence of positive integers in which, for all positive k, there are exactly k contiguous pairs whose product is k, and a(k) * a(k+1) <> a(k+1) * a(k+2).
%C A348485 This sequence is a variant of A307720 where we don't allow consecutive equal products of contiguous pairs.
%H A348485 Rémy Sigrist, <a href="/A348485/b348485.txt">Table of n, a(n) for n = 1..10000</a>
%H A348485 Rémy Sigrist, <a href="/A348485/a348485.gp.txt">PARI program for A348485</a>
%e A348485 The first terms, alongside a(n)*a(n+1), are:
%e A348485   n   a(n)  a(n)*a(n+1)
%e A348485   --  ----  -----------
%e A348485    1     1            1
%e A348485    2     1            2
%e A348485    3     2            4
%e A348485    4     2            2
%e A348485    5     1            3
%e A348485    6     3            6
%e A348485    7     2            4
%e A348485    8     2            6
%e A348485    9     3            3
%e A348485   10     1            4
%e A348485   11     4            8
%e A348485   12     2            4
%e A348485   13     2            6
%e A348485   14     3            3
%e A348485   15     1            5
%o A348485 (PARI) See Links section.
%Y A348485 Cf. A307720, A348486 (the products).
%K A348485 nonn
%O A348485 1,3
%A A348485 _Rémy Sigrist_, Oct 21 2021