a(n) is the smallest number whose name in US English contains n consonants.

Terms

a(0) =1a(1) =2a(2) =3a(3) =12a(4) =13a(5) =22a(6) =23a(7) =102a(8) =103a(9) =112a(10) =113a(11) =122a(12) =123a(13) =223a(14) =323a(15) =1112a(16) =1113a(17) =1122a(18) =1123a(19) =1223a(20) =1323a(21) =2323a(22) =3323a(23) =12323a(24) =13323a(25) =22323a(26) =23323a(27) =102323a(28) =103323a(29) =112323