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%I #23 Apr 30 2022 12:18:49
%S 0,1,2,3,4,5,6,7,8,9,10,20,30,34,40,43,50,60,68,70,80,86,90,100,122,
%T 148,184,200,212,221,236,244,263,269,296,300,304,326,340,362,366,400,
%U 403,418,424,430,442,447,474,481,488,500,600,608,623,629,632,636,663
%N Numbers whose sum of squares of digits is a square.
%C Previous name: Numbers n such that Sum_{i=1..r, x(i)^2} is a perfect square, where x(i) = digits of n. r=1+floor(log_10 n).
%H Christian N. K. Anderson, <a href="/A175396/b175396.txt">Table of n, a(n) for n = 1..10000</a>
%e 34 is a term: 3^2 + 4^2 = 25 = 5^2.
%e 122 is a term: 1^2 + 2^2 + 2^2 = 9 = 3^2.
%t Select[Range[0, 666], IntegerQ[Sqrt[Plus @@ (IntegerDigits[#]^2)]] &] (* _Ivan Neretin_, Aug 03 2015 *)
%o (PARI) isok(n) = {digs = Vec(Str(n)); issquare(sum(i=1, #digs, eval(digs[i])^2))} \\ _Michel Marcus_, Jun 02 2013
%Y Cf. A084561.
%K base,easy,nonn
%O 1,3
%A _Ctibor O. Zizka_, Apr 30 2010
%E Corrected and extended by Neven Juric, Jul 12 2010
%E Simpler definition by _Michel Marcus_, Jun 02 2013
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