OFFSET
1,1
MATHEMATICA
opct47Q[n_]:=Module[{sqrt=Sqrt[n], cf, len}, cf=If[IntegerQ[sqrt], {}, ContinuedFraction[sqrt][[2]]]; len=Length[cf]; OddQ[len] && cf[[Floor[len/2]+1]] == 47] (* Harvey P. Dale, Sep 19 2012 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
EXTENSIONS
Corrected by Harvey P. Dale, Sep 19 2012
STATUS
approved