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%I #12 Jan 30 2023 02:35:54
%S 17,33,36,40,41,50,52,57,65,68,72,73,76,80,81,85,89,97,104,108,109,
%T 113,116,117,125,129,130,132,133,136,137,144,145,148,152,153,157,160,
%U 164,170,172,177,180,185,189,193,197,200,201,204,205,208,209,216,221
%N Numbers having at least two representations as a sum of two powerful numbers (A001694).
%H Amiram Eldar, <a href="/A085255/b085255.txt">Table of n, a(n) for n = 1..10000</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PowerfulNumber.html">Powerful Number</a>.
%F A085252(a(n)) > 1.
%t With[{m = 222}, pow = Select[Range[m], # == 1 || Min[FactorInteger[#][[;; , 2]]] > 1 &]; Position[BinCounts[Select[Plus @@@ Union[Sort /@ Tuples[pow, {2}]], # <= m &], {1, m, 1}], _?(# > 1 &)] // Flatten] (* _Amiram Eldar_, Jan 30 2023 *)
%Y Cf. A001694, A076871, A085252, A085253, A085254.
%K nonn
%O 1,1
%A _Reinhard Zumkeller_, Jun 23 2003