Erroneous version of A000452.

Terms

a(0) =1a(1) =2a(2) =3a(3) =5a(4) =6a(5) =7a(6) =8a(7) =10a(8) =11a(9) =11a(10) =13a(11) =14a(12) =15a(13) =16a(14) =17a(15) =19a(16) =21a(17) =22a(18) =23a(19) =24a(20) =26a(21) =27a(22) =29a(23) =30a(24) =31a(25) =33a(26) =34a(27) =35a(28) =37a(29) =38