Earliest sequence where a(a(n))=number of partitions of n.

Terms

a(0) =1a(1) =1a(2) =2a(3) =3a(4) =6a(5) =11a(6) =5a(7) =56a(8) =9a(9) =22a(10) =12a(11) =7a(12) =42a(13) =14a(14) =101a(15) =526823a(16) =17a(17) =231a(18) =19a(19) =385a(20) =21a(21) =627a(22) =30a(23) =24a(24) =1255a(25) =26a(26) =1958a(27) =28a(28) =3010a(29) =31