a(n) = smallest k such that k=a(n-k-1) is the only appearance of k so far; if there is no such k, then a(n) = least positive integer that has not yet appeared.
A026272
a(n) = smallest k such that k=a(n-k-1) is the only appearance of k so far; if there is no such k, then a(n) = least positive integer that has not yet appeared.
Terms
- a(0) =1a(1) =2a(2) =1a(3) =3a(4) =2a(5) =4a(6) =5a(7) =3a(8) =6a(9) =7a(10) =4a(11) =8a(12) =5a(13) =9a(14) =10a(15) =6a(16) =11a(17) =7a(18) =12a(19) =13a(20) =8a(21) =14a(22) =15a(23) =9a(24) =16a(25) =10a(26) =17a(27) =18a(28) =11a(29) =19
External references
- oeis: A026272