Number of subsets of {1,.., n} containing exactly one square.

Terms

a(0) =1a(1) =2a(2) =4a(3) =8a(4) =16a(5) =32a(6) =64a(7) =128a(8) =192a(9) =384a(10) =768a(11) =1536a(12) =3072a(13) =6144a(14) =12288a(15) =16384a(16) =32768a(17) =65536a(18) =131072a(19) =262144a(20) =524288a(21) =1048576a(22) =2097152a(23) =4194304a(24) =5242880a(25) =10485760a(26) =20971520a(27) =41943040a(28) =83886080a(29) =167772160