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%I #9 Apr 20 2020 19:13:05
%S 3,10,17,36,60,84,88,96,104,108,132,136,144,152,156,168,180,184,192,
%T 204,208,216,228,232,240,248,252,264,276,288,296,300,312,324,328,336,
%U 344,348,352,372,376,384,392,396,400,408,420,424,444,456,459,468,472
%N Sums of two distinct refactorable numbers whose product and difference are refactorable.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/RefactorableNumber.html">Refactorable Number</a>
%t Flatten[Table[If[Sum[ (1 - Ceiling[(n - 2 i)/DivisorSigma[0, n - 2 i]] + Floor[(n - 2 i)/DivisorSigma[0, n - 2 i]]) (1 - Ceiling[(i (n - i))/DivisorSigma[0, i (n - i)]] + Floor[(i (n - i))/DivisorSigma[0, i (n - i)]]) (1 - Ceiling[i/DivisorSigma[0, i]] + Floor[i/DivisorSigma[0, i]]) (1 - Ceiling[(n - i)/DivisorSigma[0, n - i]] + Floor[(n - i)/DivisorSigma[0, n - i]]), {i, Floor[(n - 1)/2]}] > 0, n, {}], {n, 500}]]
%Y Cf. A033950.
%K nonn
%O 1,1
%A _Wesley Ivan Hurt_, Jul 24 2019
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