Duplicate of A030739.

Terms

a(0) =1a(1) =2a(2) =2a(3) =4a(4) =5a(5) =7a(6) =9a(7) =11a(8) =13a(9) =15a(10) =18a(11) =20a(12) =22a(13) =23a(14) =24a(15) =30a(16) =32a(17) =35a(18) =38a(19) =42a(20) =46a(21) =49a(22) =53a(23) =55a(24) =57a(25) =60a(26) =64a(27) =70