a(n) is the least k that is a multiple of d=A240991(n), with abundancy ratio sigma(k)/k equal to (sigma(d)+1)/d, or -1 if no such k exists.

A387405

a(n) is the least k that is a multiple of d=A240991(n), with abundancy ratio sigma(k)/k equal to (sigma(d)+1)/d, or -1 if no such k exists.

Terms

    a(0) =18a(1) =54a(2) =196a(3) =1521a(4) =486a(5) =1372a(6) =15376a(7) =24025a(8) =4374a(9) =1032256a(10) =67228a(11) =39366a(12) =476656a(13) =257049a(14) =744775a(15) =27237961a(16) =354294a(17) =3341637a(18) =3294172a(19) =23088025a(20) =870899121a(21) =131096512a(22) =3188646a(23) =4990433449a(24) =18837288001a(25) =28697814a(26) =43647148561a(27) =458066416a(28) =161414428a(29) =131785698529

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