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Numbers n such that the binary XOR of the divisors of n (A178910) is a binary palindrome (A006995) and not a power of 2 (A000079).
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%I #11 Aug 20 2013 13:25:21

%S 81,162,169,324,338,648,676,1296,1352,2401,2592,2704,3249,4802,5184,

%T 5408,6498,9604,10368,10816,12996,19208,20736,21632,25992,38416,41472,

%U 43264,51984,76832,82944,86528,103968,112225,153664,165888,173056,194481

%N Numbers n such that the binary XOR of the divisors of n (A178910) is a binary palindrome (A006995) and not a power of 2 (A000079).

%C A takeoff of A227843.

%t f[n_] := Fold[ BitXor[#1, #2] &, 0, Divisors@ n]; palQ[n_Integer, base_Integer] := Module[{idn = IntegerDigits[n, base]}, idn == Reverse@ idn]; fQ[n_] := palQ[ f@ n, 2] && ! IntegerQ@ Log2@ n; Select[ Range@ 200000, fQ]

%Y Cf. A000079, A006995, A178910, A227843.

%K nonn,base

%O 1,1

%A _Robert G. Wilson v_, Aug 18 2013