A278064 - OEIS

%I #15 May 30 2024 16:58:39

%S 1,2,3,4,5,6,7,8,9,10,11,12,3,13,14,5,15,6,7,16,18,10,8,18,22,12,19,

%T 14,24,11,23,27,16,13,17,15,26,20,10,27,36,20,15,42,14,31,21,34,28,15,

%U 23,50,14,31,54,24,19,23,42,32,31,34,51,14,36,61,29,17,77

%N Relative of Hofstadter Q-sequence: a(n) = n for 1 <= n <= 12; a(n) = a(n-a(n-1)) + a(n-a(n-2)) for n > 12.

%C Similar to Hofstadter's Q-sequence A005185 but with different starting values.

%C This sequence has exactly 69 terms, since a(69)=77 and computing a(70) would refer to a(-7).

%H Nathan Fox, <a href="/A278064/b278064.txt">Table of n, a(n) for n = 1..69</a>

%H Nathan Fox, <a href="https://vimeo.com/191094180">Hofstadter-like Sequences over Nonstandard Integers</a>, Talk given at the Rutgers Experimental Mathematics Seminar, November 10 2016.

%t a[n_] := a[n] = If[0 < n < 13, n, a[n-a[n-1]] + a[n-a[n-2]]];

%t Array[a, 69] (* _Paolo Xausa_, May 30 2024 *)

%Y Cf. A005185, A278056, A278057, A278058, A278059, A278060, A278061, A278062, A278063, A278065.

%K nonn,fini,full

%O 1,2

%A _Nathan Fox_, Nov 10 2016