OFFSET
1,1
MATHEMATICA
Transpose[SequencePosition[Table[If[SequenceCount[IntegerDigits[n, 7], {6, 6}]>0, 1, 0], {n, 2100}], {0, 1}]][[2]] (* The program uses the SequencePosition and SequenceCount functions from Mathematica version 10 *) (* Harvey P. Dale, May 31 2016 *)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
STATUS
approved