a(1) = 1; a(n) = a(n-1) + 2 * a(floor(n/2)).

Terms

a(0) =1a(1) =3a(2) =5a(3) =11a(4) =17a(5) =27a(6) =37a(7) =59a(8) =81a(9) =115a(10) =149a(11) =203a(12) =257a(13) =331a(14) =405a(15) =523a(16) =641a(17) =803a(18) =965a(19) =1195a(20) =1425a(21) =1723a(22) =2021a(23) =2427a(24) =2833a(25) =3347a(26) =3861a(27) =4523a(28) =5185a(29) =5995