Numbers n such that n, 2n, 3n are all highly composite numbers.

Terms

a(0) =2a(1) =12a(2) =60a(3) =120a(4) =840a(5) =2520a(6) =5040a(7) =27720a(8) =55440a(9) =110880a(10) =166320a(11) =720720a(12) =1441440a(13) =2162160a(14) =3603600a(15) =7207200a(16) =10810800a(17) =36756720a(18) =61261200a(19) =122522400a(20) =183783600a(21) =367567200a(22) =698377680a(23) =2327925600a(24) =3491888400a(25) =6983776800a(26) =13967553600a(27) =48886437600a(28) =80313433200a(29) =160626866400