OFFSET
1,1
MATHEMATICA
Transpose[SequencePosition[Table[If[SequenceCount[IntegerDigits[n, 7], {4, 4}]>0, 1, 0], {n, 2000}], {1, 0}]][[1]] (* The program uses the SequencePosition and SequenceCount functions from Mathematica version 10 *) (* Harvey P. Dale, May 01 2015 *)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
STATUS
approved