Least k such that d(k*n) = d(n!) (d = A000005).

Terms

a(0) =1a(1) =1a(2) =2a(3) =6a(4) =24a(5) =120a(6) =720a(7) =3465a(8) =18480a(9) =194040a(10) =2293200a(11) =19219200a(12) =301593600a(13) =1163962800a(14) =6518191680a(15) =20078358300a(16) =548021073600