a(n) = ceiling(g(A000073(n))) with g(k) = (k-1)^2/(4k).

Terms

a(0) =0a(1) =0a(2) =1a(3) =1a(4) =2a(5) =3a(6) =6a(7) =11a(8) =20a(9) =37a(10) =69a(11) =126a(12) =232a(13) =426a(14) =784a(15) =1442a(16) =2652a(17) =4878a(18) =8973a(19) =16503a(20) =30354a(21) =55829a(22) =102686a(23) =188869a(24) =347384a(25) =638939a(26) =1175193a(27) =2161516a(28) =3975648a(29) =7312356