Number of subsets of [n] in which exactly half of the elements are powers of 2.

Terms

a(0) =1a(1) =1a(2) =1a(3) =3a(4) =4a(5) =10a(6) =20a(7) =35a(8) =70a(9) =126a(10) =210a(11) =330a(12) =495a(13) =715a(14) =1001a(15) =1365a(16) =4368a(17) =6188a(18) =8568a(19) =11628a(20) =15504a(21) =20349a(22) =26334a(23) =33649a(24) =42504a(25) =53130a(26) =65780a(27) =80730a(28) =98280a(29) =118755