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A335143 Nonunitary Zumkeller numbers (A335142) whose set of nonunitary divisors can be partitioned into two disjoint sets of equal sum in a single way. 4

%I #5 May 25 2020 09:27:20

%S 24,48,54,80,112,150,224,280,294,352,416,630,704,726,832,1014,1088,

%T 1216,1472,1734,1750,1856,1984,2166,2475,2944,3174,3344,3430,3712,

%U 3968,4275,4736,5046,5248,5504,5766,6016,6784,7552,7808,8214,8470,10086,11008,11094

%N Nonunitary Zumkeller numbers (A335142) whose set of nonunitary divisors can be partitioned into two disjoint sets of equal sum in a single way.

%e 24 is a term since there is only one partition of its set of nonunitary divisors, {2, 4, 6, 12}, into two disjoint sets of equal sum: {2, 4, 6} and {12}.

%t nuzQ[n_] := Module[{d = Select[Divisors[n], GCD[#, n/#] > 1 &], sum, x}, sum = Plus @@ d; sum > 0 && EvenQ[sum] && CoefficientList[Product[1 + x^i, {i, d}], x][[1 + sum/2]] == 2]; Select[Range[12000], nuzQ]

%Y The nonunitary version of A083209.

%Y Subsequence of A335142.

%K nonn

%O 1,1

%A _Amiram Eldar_, May 25 2020

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Last modified April 25 01:06 EDT 2024. Contains 371964 sequences. (Running on oeis4.)