OFFSET
1,1
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000.
FORMULA
a(n) = sqrt(A192689(n)).
EXAMPLE
34 is in the sequence because 34^2 = 1156 but neither 156, 56 nor 6 are perfect squares.
36 is in the sequence because 36^2 = 1296 but neither 296, 96 nor 6 are perfect squares.
44 is not in the sequence because 44^2 = 1936 and 36 = 6^2.
MATHEMATICA
nfgsQ[n_]:=Module[{s=n^2}, NoneTrue[FromDigits/@Rest[NestList[ Rest, IntegerDigits[ s], IntegerLength[ s]-1]], IntegerQ[Sqrt[#]]&]]; Select[ Range[ 4, 500], nfgsQ] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, May 18 2019 *)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
J. Lowell, May 03 2014
STATUS
approved