a(n) is the number of unlabeled rank-3 graded lattices with 5 coatoms and n atoms.

Terms

a(0) =1a(1) =5a(2) =20a(3) =68a(4) =190a(5) =441a(6) =907a(7) =1690a(8) =2916a(9) =4734a(10) =7310a(11) =10836a(12) =15528a(13) =21619a(14) =29365a(15) =39045a(16) =50961a(17) =65434a(18) =82809a(19) =103453a(20) =127751a(21) =156117a(22) =188980a(23) =226794a(24) =270037a(25) =319204a(26) =374813a(27) =437409a(28) =507553a(29) =585831