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Ternary numbers that are concatenated runs A(1)B(1)C(1)A(2)B(2)C(2)...A(k)B(k)C(k), where A(i) is a run of 1's, B(i) a run of 0's, and C(i) a run of 2's, for i = 1..k.
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%I #16 Apr 04 2024 10:28:23

%S 102,1002,1022,1102,10002,10022,10222,11002,11022,11102,100002,100022,

%T 100222,102102,102222,110002,110022,110222,111002,111022,111102,

%U 1000002,1000022,1000222,1002102,1002222,1021002,1021022,1021102,1022102,1022222,1100002

%N Ternary numbers that are concatenated runs A(1)B(1)C(1)A(2)B(2)C(2)...A(k)B(k)C(k), where A(i) is a run of 1's, B(i) a run of 0's, and C(i) a run of 2's, for i = 1..k.

%e 1021002 has the form A(1)B(1)C(1)A(2)B(2)C(2), where A(1) = 1, B(1) = 0, C(1)=2, A(2)= 1, B(2) = 00, and C(2) = 2.

%t Map[#[[1]] &, Select[Map[{#, DeleteDuplicates[Partition[Map[#[[1]] &, Split[IntegerDigits[#, 3]]], UpTo[3]]] == {{1, 0, 2}}} &,

%t Range[2, 2800, 3]], #[[2]] &]] (* this sequence *)

%t m = Map[{#, IntegerString[#, 3]} &, %];

%t Map[Last, ToExpression[m]] (* A371106 *)

%t (* _Peter J. C. Moses_, Mar 06 2024 *)

%Y Cf. A007089, A371106, A371107, A371108, A371109, A371110, A371111, A371112.

%K nonn,base

%O 1,1

%A _Clark Kimberling_, Mar 22 2024