Untouchable cubes.

Terms

a(0) =216a(1) =1728a(2) =5832a(3) =8000a(4) =13824a(5) =21952a(6) =27000a(7) =74088a(8) =110592a(9) =157464a(10) =175616a(11) =195112a(12) =216000a(13) =238328a(14) =287496a(15) =314432a(16) =343000a(17) =373248a(18) =729000a(19) =884736a(20) =941192a(21) =1061208a(22) =1124864a(23) =1259712a(24) =1481544a(25) =1728000a(26) =2000376a(27) =2097152a(28) =2628072a(29) =2744000