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 A269265 #29 Sep 08 2022 08:46:15
%S A269265 1,1,2,4,6,36,42,1764,1806,3261636,3263442,10650053687364,
%T A269265 10650056950806,113423713055411194304049636,
%U A269265 113423713055421844361000442,12864938683278671740537145884937248491231415124195364,12864938683278671740537145998360961546653259485195806
%N A269265 a(0) = a(1) = 1; thereafter a(n) = a(n-1) + a(n-2) if n is even, otherwise a(n) = a(n-1)^2.
%C A269265 The first bisection is A007018, the second bisection is A174864 (with an only initial 1).
%C A269265 After 2, all terms belong to A238411.
%F A269265 a(n) = ( 1 + Sum_{k=0..floor(n/2)-1} a(2*k+1) )^(3-(-1)^n)/2 for n>1.
%t A269265 a[n_] := If[OddQ@n, a[n - 1] + a[n - 2], a[n - 1]^2]; a[0] = 1; Array[a, 17]
%o A269265 (Magma) [n le 2 select 1 else IsEven(n) select Self(n-1)^2 else Self(n-1)+Self(n-2): n in [1..20]];
%Y A269265 Cf. A007018, A174864, A238411.
%K A269265 nonn
%O A269265 0,3
%A A269265 _Vincenzo Librandi_, Feb 23 2016
%E A269265 Edited and extended by _Bruno Berselli_, Feb 25 2016