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A371105
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.
7
102, 1002, 1022, 1102, 10002, 10022, 10222, 11002, 11022, 11102, 100002, 100022, 100222, 102102, 102222, 110002, 110022, 110222, 111002, 111022, 111102, 1000002, 1000022, 1000222, 1002102, 1002222, 1021002, 1021022, 1021102, 1022102, 1022222, 1100002
OFFSET
1,1
EXAMPLE
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.
MATHEMATICA
Map[#[[1]] &, Select[Map[{#, DeleteDuplicates[Partition[Map[#[[1]] &, Split[IntegerDigits[#, 3]]], UpTo[3]]] == {{1, 0, 2}}} &,
Range[2, 2800, 3]], #[[2]] &]] (* this sequence *)
m = Map[{#, IntegerString[#, 3]} &, %];
Map[Last, ToExpression[m]] (* A371106 *)
(* Peter J. C. Moses, Mar 06 2024 *)
KEYWORD
nonn,base
AUTHOR
Clark Kimberling, Mar 22 2024
STATUS
approved