OFFSET
1,1
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..1600
MATHEMATICA
Select[Range[1400], Min[Length/@Split[IntegerDigits[#, 4]]]>1&] (* Harvey P. Dale, Jun 05 2013 *)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
STATUS
approved