Cubes written in base 4.

Terms

a(0) =1a(1) =20a(2) =123a(3) =1000a(4) =1331a(5) =3120a(6) =11113a(7) =20000a(8) =23121a(9) =33220a(10) =110303a(11) =123000a(12) =202111a(13) =222320a(14) =310233a(15) =1000000a(16) =1030301a(17) =1123020a(18) =1223023a(19) =1331000a(20) =2100231a(21) =2212120a(22) =2332013a(23) =3120000a(24) =3310021a(25) =10102220a(26) =10303203a(27) =11113000a(28) =11331011a(29) =12211320