cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A278057 Relative of Hofstadter Q-sequence: a(n) = n for 1 <= n <= 5; a(n) = a(n-a(n-1)) + a(n-a(n-2)) for n > 5.

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%I A278057 #18 May 29 2024 15:14:44
%S A278057 1,2,3,4,5,3,6,7,5,8,6,7,9,11,7,10,14,11,12,12,10,15,16,12,14,18,14,
%T A278057 19,15,13,21,18,14,22,19,25,18,21,21,24,26,21,29,23,25,26,25,31,23,26,
%U A278057 33,30,28,30,28,37,27,31,37,31,25,39
%N A278057 Relative of Hofstadter Q-sequence: a(n) = n for 1 <= n <= 5; a(n) = a(n-a(n-1)) + a(n-a(n-2)) for n > 5.
%C A278057 Similar to Hofstadter's Q-sequence A005185 but with different starting values.
%C A278057 Much like the Hofstadter Q-sequence, it is not known if this sequence is defined for all positive n.
%C A278057 a(n) exists for n <= 3*10^7.
%H A278057 Nathan Fox, <a href="/A278057/b278057.txt">Table of n, a(n) for n = 1..10000</a>
%H A278057 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 A278057 a[n_] := a[n] = If[0 < n < 6, n, a[n-a[n-1]] + a[n-a[n-2]]];
%t A278057 Array[a, 100] (* _Paolo Xausa_, May 29 2024 *)
%Y A278057 Cf. A005185, A278056, A278058, A278059, A278060, A278061, A278062, A278063, A278064, A278065.
%K A278057 nonn
%O A278057 1,2
%A A278057 _Nathan Fox_, Nov 10 2016