Number of isomorphism classes of reduced Witt rings of fields with 2n orderings.

Terms

a(0) =1a(1) =2a(2) =3a(3) =6a(4) =9a(5) =16a(6) =24a(7) =42a(8) =64a(9) =105a(10) =159a(11) =258a(12) =390a(13) =614a(14) =925a(15) =1441a(16) =2162a(17) =3317a(18) =4951a(19) =7526a(20) =11191a(21) =16841a(22) =24923a(23) =37253a(24) =54912a(25) =81493a(26) =119629a(27) =176549a(28) =258205a(29) =379025