Variant of the factorial base representation of n.

Terms

a(0) =1a(1) =11a(2) =101a(3) =111a(4) =201a(5) =211a(6) =1001a(7) =1011a(8) =1101a(9) =1111a(10) =1201a(11) =1211a(12) =2001a(13) =2011a(14) =2101a(15) =2111a(16) =2201a(17) =2211a(18) =3001a(19) =3011a(20) =3101a(21) =3111a(22) =3201a(23) =3211a(24) =10001a(25) =10011a(26) =10101a(27) =10111a(28) =10201a(29) =10211