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%I #10 Apr 25 2023 13:51:38
%S 6300100,7502121,16654561,57942544,74753316,696379321,1185424900,
%T 2176315801,16960113361,21735899761,44504965444,52141439025,
%U 95610824100,105593152401,189565322881,213454164121,293481144121,527475375625
%N Squares which form nonzero squares when their reversal is subtracted from them.
%e a(2) = 2739^2 = 7502121 => 7502121 - 1212057 = 6290064 = 2508^2.
%t 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 *)
%o (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
%K nonn,base
%O 1,1
%A _Gaurav Kumar_, Jul 24 2009
%E Definition clarified by _Michel Marcus_, Jun 02 2013
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