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A371055
Ternary numbers consisting of a run of 1's, then a run of 0's, then a run of 2's.
1
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
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
KEYWORD
nonn,base
AUTHOR
Clark Kimberling, Mar 22 2024
STATUS
approved