A373228 - OEIS

%I #10 May 31 2024 14:33:49

%S 1,2,3,4,5,6,7,8,6,9,10,11,9,12,13,14,12,15,16,17,15,18,19,17,21,18,

%T 21,23,24,19,26,23,28,24,28,27,24,31,32,28,24,36,36,33,23,37,38,40,27,

%U 39,38,42,35,41,38,43,42,44,39,44,42,51,42,45,48,47,51,44,54,48,52,49,53

%N Relative of Hofstadter Q-sequence: a(n) = n for 1 <= n <= 8; a(n) = a(n-a(n-1)) + a(n-a(n-2)) + a(n-a(n-3)) for n > 8.

%C Similar to A278055 but with different starting values.

%C Much like the Hofstadter Q-sequence A005185, it is not known if this sequence is defined for all positive n.

%C a(n) exists for n <= 3*10^7.

%H Nathan Fox, <a href="/A373228/b373228.txt">Table of n, a(n) for n = 1..10000</a>

%t a[n_] := a[n] = If[0 < n < 9, n, a[n-a[n-1]] + a[n-a[n-2]] + a[n-a[n-3]]];

%t Array[a, 100] (* _Paolo Xausa_, May 31 2024 *)

%Y Cf. A005185, A278055, A373227, A373229, A373230, A373231, A373232, A373233.

%Y Similar sequences based on the Q-recurrence: A278056, A278057, A278058, A278059, A278060, A278061, A278062, A278063, A278064, A278065.

%K nonn

%O 1,2

%A _Nathan Fox_, May 28 2024