OFFSET
1,1
MATHEMATICA
Transpose[SequencePosition[Table[If[SequenceCount[IntegerDigits[n, 7], {3, 3}]>0, 1, 0], {n, 3000}], {1, 0}]][[1]] (* The program uses the SequencePosition and SequenceCount functions from Mathematica version 10 *) (* Harvey P. Dale, May 18 2015 *)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
STATUS
approved