A371055 Ternary numbers consisting of a run of 1's, then a run of 0's, then a run of 2's.

102, 1002, 1022, 1102, 10002, 10022, 10222, 11002, 11022, 11102, 100002, 100022, 100222, 102222, 110002, 110022, 110222, 111002, 111022, 111102, 1000002, 1000022, 1000222, 1002222, 1022222, 1100002, 1100022, 1100222, 1102222, 1110002, 1110022, 1110222

Offset

1,1

Links

Table of n, a(n) for n=1..32.

Example

10002 consists of a run 1, then a run 000, then a run 2.

Mathematica

Map[#[[1]] &, Select[Map[{#, Map[#[[1]] &, Split[IntegerDigits[#, 3]]] == {1, 0, 2}} &, Range[2, 4000, 3]], #[[2]] &]]  (* A370543 *)
ToExpression[Map[IntegerString[#, 3] &, %]]  (* this sequence *)
(* Peter J. C. Moses, Mar 06 2024 *)

Prog

(Python)
from itertools import count, islice
def A371055_gen(): # generator of terms
    return (10**(l-a)*((10**a-1)//9)+((10**b-1)//9<<1) for l in count(3) for a in range(1, l-1) for b in range(1, l-a))
A371055_list = list(islice(A371055_gen(), 20)) # Chai Wah Wu, Mar 25 2024

Crossrefs

Cf. A007089, A371054

Sequence in context: A230704 A151964 A371105 * A088805 A206171 A199830

Adjacent sequences: A371052 A371053 A371054 * A371056 A371057 A371058

Keyword

nonn,base

Author

Clark Kimberling, Mar 22 2024

Status

approved