a(n) is the index where A387090(n) appears in A386482.

Terms

a(0) =1a(1) =2a(2) =5a(3) =17a(4) =24a(5) =44a(6) =52a(7) =73a(8) =126a(9) =809a(10) =821a(11) =1016a(12) =2020a(13) =2026a(14) =2637a(15) =3017a(16) =3541a(17) =3544a(18) =4876a(19) =12680a(20) =12803a(21) =12808a(22) =12898a(23) =12901a(24) =12907a(25) =13279a(26) =17729a(27) =17734a(28) =27224a(29) =33351