Nimsum n + 15.

Terms

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