a(n) = number of refinements of the partition n^1.

Terms

a(0) =1a(1) =2a(2) =3a(3) =7a(4) =15a(5) =43a(6) =131a(7) =468a(8) =1776a(9) =7559a(10) =34022a(11) =166749a(12) =853823a(13) =4682358a(14) =26720781a(15) =161074458a(16) =1004485751a(17) =6576974188a(18) =44322716809a(19) =311440019349