a(n) = Sum_{k=0..floor(n/2)} k*binomial(n,k).

Terms

a(0) =0a(1) =0a(2) =2a(3) =3a(4) =16a(5) =25a(6) =96a(7) =154a(8) =512a(9) =837a(10) =2560a(11) =4246a(12) =12288a(13) =20618a(14) =57344a(15) =97140a(16) =262144a(17) =447661a(18) =1179648a(19) =2028478a(20) =5242880a(21) =9070110a(22) =23068672a(23) =40122028a(24) =100663296a(25) =175913250a(26) =436207616a(27) =765561564a(28) =1879048192a(29) =3310623412