a(n)=least k such that s(k)=n, where s=A030707.

Terms

a(0) =1a(1) =7a(2) =3a(3) =4a(4) =16a(5) =6a(6) =29a(7) =9a(8) =38a(9) =30a(10) =14a(11) =39a(12) =20a(13) =51a(14) =84a(15) =28a(16) =152a(17) =37a(18) =82a(19) =124a(20) =83a(21) =49a(22) =177a(23) =101a(24) =64a(25) =276a(26) =123a(27) =81a(28) =146a(29) =99