Ceiling(n/2)-perfect numbers.

Terms

a(0) =2a(1) =4a(2) =8a(3) =10a(4) =16a(5) =32a(6) =64a(7) =110a(8) =128a(9) =136a(10) =256a(11) =512a(12) =884a(13) =1024a(14) =2048a(15) =4096a(16) =8192a(17) =16384a(18) =18632a(19) =32768a(20) =32896a(21) =65536a(22) =70564a(23) =100804a(24) =116624a(25) =131072a(26) =262144a(27) =391612a(28) =449295a(29) =524288