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.
%I A078108 #18 Jun 16 2025 20:16:43
%S A078108 4,24,156,184,324,608,940,1784,1844,3104,5996,4600,4484,6128,6220,
%T A078108 7208,8244,9424,11740,13560,14836,19264,19756,23344,24524,26224,32940,
%U A078108 34912,34548,42808,52428,46120,47492,52280,67908,86120,80084,147152
%N A078108 Let u(1)=u(2)=1, u(3)=2n, u(k) = abs(u(k-1)-u(k-2)-u(k-3)) and M(k) = Max_{i<=i<=k} u(i), then for any k >= A078109(n), M(k) = floor(sqrt(k + a(n))).
%C A078108 It appears that (1) a(n) always exists, (2) a(n) is even, (3) a(n)/n^(5/2) -> infinity. If initial conditions are u(1)=u(2)=1, u(3)=2n+1, then u(k) reaches a 2-cycle for any k>m large enough (cf. A078098). - _Benoit Cloitre_, Jan 29 2006
%Y A078108 Cf. A000196, A078109, A077623, A078098.
%K A078108 nonn
%O A078108 1,1
%A A078108 _Benoit Cloitre_, Dec 05 2002
%E A078108 Typos in data corrected by _Sean A. Irvine_, Jun 16 2025