a(n) is the smallest k such that tau(2*k) is equal to 2^n, where tau = A000005.

A380836

a(n) is the smallest k such that tau(2*k) is equal to 2^n, where tau = A000005.

Terms

    a(0) =1a(1) =3a(2) =12a(3) =60a(4) =420a(5) =3780a(6) =41580a(7) =540540a(8) =8648640a(9) =147026880a(10) =2793510720a(11) =64250746560

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