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Numbers n such that sum of squares of digits of n is a power of 2.
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%I #11 Mar 30 2012 18:35:52

%S 1,2,4,8,10,11,20,22,40,44,80,88,100,101,110,200,202,220,400,404,440,

%T 800,808,880,1000,1001,1010,1100,1111,2000,2002,2020,2200,2222,4000,

%U 4004,4040,4400,4444,8000,8008,8080,8800,8888

%N Numbers n such that sum of squares of digits of n is a power of 2.

%e 11369 is in the sequence because 1^2+1^2+3^2+6^2+9^2 = 128 = 2^7.

%t Select[Range[100000], IntegerQ[Log[2, Plus @@ (IntegerDigits[#]^2)]] &]

%K nonn,base

%O 1,2

%A _Michel Lagneau_, Nov 29 2010