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%I #14 Jan 21 2019 12:52:31
%S 10,11,12,13,14,15,18,20,21,22,23,30,31,90,100,200,263,265,300,900,
%T 985,1000,1002,2000,2001,3000,5265,9000,10000,10002,10020,20000,20001,
%U 20010,30000,90000,100000,100002,100020,100200,200000,200001,200010,200100,262987,300000,900000,1000000,1000002,1000020,1000200,1002000,2000000,2000001,2000010,2000100,2001000,2001002,3000000
%N Sum of any three adjacent digits of n^2 is a square.
%e 262987^2=69162162169 and 6+9+1=16, 9+1+6=16, 1+6+2=9, 6+2+1=9, 2+1+6=9, 1+6+2=9, 6+2+1=9, 2+1+6=9, 1+6+9=16 are all squares.
%t s={};Do[id=IntegerDigits[n^2];
%t If[Union[IntegerQ/@(Sqrt[Total/@Partition[id,3,1]])]=={True},Print[n];AppendTo[s,n]],{n,10,3*10^6}]
%t Select[Range[10,3*10^6],AllTrue[Total/@Partition[IntegerDigits[#^2],3,1], IntegerQ[ Sqrt[#]]&]&] (* _Harvey P. Dale_, Jan 21 2019 *)
%Y Cf.A061910 Numbers n such that sum of digits of n^2 is a square.
%K nonn,base
%O 1,1
%A _Zak Seidov_, Nov 28 2010
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