OFFSET
1,1
EXAMPLE
a(2) = 2739^2 = 7502121 => 7502121 - 1212057 = 6290064 = 2508^2.
MATHEMATICA
nzsQ[n_]:=Module[{c=Sqrt[n-FromDigits[Reverse[IntegerDigits[n]]]]}, c!=0 && IntegerQ[c]]; Select[Range[750000]^2, nzsQ] (* Harvey P. Dale, Aug 03 2013 *)
PROG
(PARI) reverse(expr)=my(v=Vec(Str(expr)), n=length(v)); concat(vector(n, i, v[n-i+1])); lista(nn) = {for (n=1, nn, if (issquare(n), rn = eval(reverse(n)); if (n!= rn && issquare(n-rn), print1(n, ", "))); ); } \\ Michel Marcus, Jun 02 2013
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Gaurav Kumar, Jul 24 2009
EXTENSIONS
Definition clarified by Michel Marcus, Jun 02 2013
STATUS
approved