a(n) = ceiling(A173497(n)/2).

Terms

a(0) =1a(1) =1a(2) =1a(3) =2a(4) =2a(5) =3a(6) =4a(7) =6a(8) =8a(9) =11a(10) =15a(11) =20a(12) =28a(13) =38a(14) =52a(15) =71a(16) =97a(17) =132a(18) =181a(19) =247a(20) =337a(21) =461a(22) =629a(23) =860a(24) =1174a(25) =1604a(26) =2191a(27) =2993a(28) =4089a(29) =5585