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1,1

a(11) is the smallest term for x!=y, y!=z, x!=z

If x=y=z then we get multiply unitary perfect numbers such that UnitarySigma(x)=3x/2.

Table of n, a(n) for n=1..14.

Factorization of a(11) : 17*3^2*47^2

Cf. A144673, A144674 (these entries all differ at a(11)).

Sequence in context: A196748 A144674 A144673 * A145681 A108061 A154546

Adjacent sequences: A144669 A144670 A144671 * A144673 A144674 A144675

nonn

Yasutoshi Kohmoto, Feb 02 2009

approved