Least odd number m such that m*2^n is a perfect, amicable or sociable number, and -1 if no such number exists.

A358320

Least odd number m such that m*2^n is a perfect, amicable or sociable number, and -1 if no such number exists.

Terms

    a(0) =12285a(1) =3a(2) =7a(3) =779a(4) =31a(5) =37a(6) =127a(7) =651a(8) =2927269a(9) =93a(10) =25329329a(11) =7230607a(12) =8191a(13) =66445153a(14) =7613527a(15) =18431675687a(16) =131071a(17) =264003743a(18) =524287a(19) =59592560831a(20) =949755039781

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