OFFSET
1,1
MATHEMATICA
SequencePosition[Table[If[SequenceCount[IntegerDigits[n, 4], {1, 3}]>0 || SequenceCount[IntegerDigits[n, 4], {3, 1}]>0, 1, 0], {n, 500}], {1, 0}][[All, 1]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, May 13 2020 *)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
STATUS
approved