Numbers of the form 2^i*5^j where i+j is odd.

Terms

a(0) =2a(1) =5a(2) =8a(3) =20a(4) =32a(5) =50a(6) =80a(7) =125a(8) =128a(9) =200a(10) =320a(11) =500a(12) =512a(13) =800a(14) =1250a(15) =1280a(16) =2000a(17) =2048a(18) =3125a(19) =3200a(20) =5000a(21) =5120a(22) =8000a(23) =8192a(24) =12500a(25) =12800a(26) =20000a(27) =20480a(28) =31250a(29) =32000