Boustrophedon transform of nonprimes.

Terms

a(0) =1a(1) =5a(2) =15a(3) =40a(4) =114a(5) =371a(6) =1422a(7) =6334a(8) =32238a(9) =184655a(10) =1175454a(11) =8231308a(12) =62882262a(13) =520416569a(14) =4638303786a(15) =44292536061a(16) =451160065069