OFFSET
1,1
MATHEMATICA
SequencePosition[Table[If[SequenceCount[IntegerDigits[n, 9], {1, 2}]>0 || SequenceCount[ IntegerDigits[n, 9], {2, 1}]>0, 1, 0], {n, 2000}], {0, 1}][[All, 2]] (* Harvey P. Dale, Nov 24 2022 *)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
STATUS
approved