OFFSET
1,1
COMMENTS
The bi-unitary version of A064771.
EXAMPLE
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.
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
CROSSREFS
KEYWORD
nonn
AUTHOR
Amiram Eldar, Nov 28 2017
STATUS
approved