A295830 Bi-unitary pseudoperfect numbers that equal to the sum of a subset of their aliquot bi-unitary divisors in a single way.

6, 60, 72, 78, 80, 88, 90, 102, 104, 114, 138, 150, 162, 174, 186, 222, 246, 258, 282, 294, 318, 354, 366, 402, 426, 438, 474, 498, 534, 582, 606, 618, 642, 654, 678, 704, 726, 762, 786, 822, 832, 834, 894, 906, 942, 978, 1002, 1014, 1038, 1074, 1086, 1146

Offset: 1

Author

Amiram Eldar, Nov 28 2017

Keywords

• nonn

Comments

The bi-unitary version of A064771.

Examples

			72 is in the sequence since its aliquot bi-unitary divisors are 1, 2, 4, 8, 9, 18, 36 and {1, 8, 9, 18, 36} is the only subset whose sum is 72.
		

Crossrefs

Cf. A064771, A292985.

Programs

Mathematica

f[n_] := Select[Divisors[n], Function[d, CoprimeQ[d, n/d]]]; bdiv[m_] := Select[Divisors[m], Last@Intersection[f@#, f[m/#]] == 1 &]; a={}; n=0;While[Length[a]<100,n++;d=Most[bdiv[n]];c = SeriesCoefficient[ Series[ Product[1+x^d[[i]],{i,Length[d]}],{x,0,n}],n ];If[c==1; AppendTo[a,n]]];a