OFFSET
1,2
COMMENTS
Similar to Hofstadter's Q-sequence A005185 but with different starting values.
Much like the Hofstadter Q-sequence, it is not known if this sequence is defined for all positive n.
a(n) exists for n <= 3*10^7.
LINKS
Nathan Fox, Table of n, a(n) for n = 1..10000
Nathan Fox, Hofstadter-like Sequences over Nonstandard Integers, Talk given at the Rutgers Experimental Mathematics Seminar, November 10 2016.
MATHEMATICA
a[n_] := a[n] = If[0 < n < 10, n, a[n-a[n-1]] + a[n-a[n-2]]];
Array[a, 100] (* Paolo Xausa, May 29 2024 *)
PROG
(Magma) [n le 9 select n else Self(n-Self(n-1))+Self(n-Self(n-2)): n in [1..70]]; // Bruno Berselli, Nov 15 2016
CROSSREFS
KEYWORD
nonn
AUTHOR
Nathan Fox, Nov 10 2016
STATUS
approved