a(n) = A007598(floor(n/2) - (-1)^n).

Terms

a(0) =1a(1) =1a(2) =0a(3) =1a(4) =1a(5) =4a(6) =1a(7) =9a(8) =4a(9) =25a(10) =9a(11) =64a(12) =25a(13) =169a(14) =64a(15) =441a(16) =169a(17) =1156a(18) =441a(19) =3025a(20) =1156a(21) =7921a(22) =3025a(23) =20736a(24) =7921a(25) =54289a(26) =20736a(27) =142129a(28) =54289a(29) =372100