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%I #21 May 13 2022 14:05:51
%S 1,2,3,4,5,6,7,8,9,10,11,20,12,13,14,15,16,17,18,19,21,22,30,23,24,25,
%T 26,27,28,29,31,32,33,40,34,35,36,37,38,39,41,42,43,44,50,45,46,47,48,
%U 49,51,52,53,54,55,60,56,57,58,59,61,62,63,64,65,66,70,67,68,69,71,72,73,74,75,76,77,80,78,79,81,82,83,84,85,86,87,88,90,89,91,92,93,94,95,96,97,98,99,101,102,103,104,105,106,107,108,109
%N The sequence S = a(1), a(2), ... is defined by a(1)=1, if d,e,f are consecutive digits then we do not have d >= e = f, and S is always extended with the smallest integer not yet present in S.
%C Computed by _Lars Blomberg_.
%C More than the usual number of terms are displayed, in order to show the difference from A130571. Differs from A130571 at index 91: a(91) = 91, while A130571(91) = 100.
%D Eric Angelini, Posting to Sequence Fans Mailing List, Sep 28 2013.
%H Eric Angelini, <a href="http://www.cetteadressecomportecinquantesignes.com/LittleEqualGreat.htm">Less than <, Equal to =, Greater than ></a> (see sequence St)
%H Eric Angelini, <a href="/A239083/a239083.pdf">Less than <, Equal to =, Greater than ></a> [Cached copy, with permission of the author]
%t a[1]=1;a[n_]:=a[n]=Block[{k=1},While[MemberQ[s=Array[a,n-1],k]||Or@@(#>=#2==#3&@@@Partition[Flatten[IntegerDigits/@Join[Last@s,{k}]],3,1]),k++];k];Array[a,108] (* _Giorgos Kalogeropoulos_, May 13 2022 *)
%Y The sequences in this family are given in A239083-A239086, A239136-A239139, A239087-A239090, A239215-A239218, A239235.
%Y Cf. A130571.
%K nonn,base
%O 1,2
%A _Michel Marcus_ and _N. J. A. Sloane_, Mar 12 2014