A335199 Infinitary Zumkeller numbers (A335197) whose set of infinitary divisors can be partitioned into two disjoint sets of equal sum in a single way.
6, 56, 60, 70, 72, 88, 90, 104, 3040, 3230, 3770, 4030, 4510, 5170, 5390, 5800, 5830, 6808, 7144, 7192, 7400, 7912, 8056, 8968, 9272, 9656, 9928, 10744, 10792, 11016, 11096, 11288, 11392, 12104, 12416, 12928, 13184, 13192, 13696, 13736, 13952, 14008, 14464, 14552
Offset: 1
Keywords
Examples
6 is a term since there is only one partition of its set of nonunitary divisors, {1, 2, 3, 6}, into two disjoint sets of equal sum: {1, 2, 3} and {6}.
Programs
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Mathematica
infdivs[n_] := If[n == 1, {1}, Sort @ Flatten @ Outer[Times, Sequence @@ (FactorInteger[n] /. {p_, m_Integer} :> p^Select[Range[0, m], BitOr[m, #] == m &])]]; infZumQ[n_] := Module[{d = infdivs[n], sum, x}, sum = Plus @@ d; If[sum < 2*n || OddQ[sum], False, CoefficientList[Product[1 + x^i, {i, d}], x][[1 + sum/2]] == 2]]; Select[Range[15000], infZumQ] (* after Michael De Vlieger at A077609 *)