Sums of two powers of 4.

Terms

a(0) =2a(1) =5a(2) =8a(3) =17a(4) =20a(5) =32a(6) =65a(7) =68a(8) =80a(9) =128a(10) =257a(11) =260a(12) =272a(13) =320a(14) =512a(15) =1025a(16) =1028a(17) =1040a(18) =1088a(19) =1280a(20) =2048a(21) =4097a(22) =4100a(23) =4112a(24) =4160a(25) =4352a(26) =5120a(27) =8192a(28) =16385a(29) =16388