a(n) = T(n,m) + T(n,m+1) + ... + T(n,n), where m = floor((n+2)/2), T given by A027948.

Terms

a(0) =1a(1) =1a(2) =4a(3) =5a(4) =20a(5) =32a(6) =95a(7) =169a(8) =424a(9) =793a(10) =1816a(11) =3488a(12) =7583a(13) =14789a(14) =31172a(15) =61357a(16) =126892a(17) =251200a(18) =513343a(19) =1019921a(20) =2068496a(21) =4119281a(22) =8313584a(23) =16580800a(24) =33358015a(25) =66594637a(26) =133703500a(27) =267089189a(28) =535524644a(29) =1070217248