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 A346707 #24 Aug 21 2021 00:15:59
%S A346707 1,2,2,1,2,1,2,1,2,1,2,2,2,1,2,1,2,1,2,2,1,1,2,1,2,1,2,2,2,1,2,1,2,1,
%T A346707 2,2,1,2,2,1,2,1,2,2,2,1,2,1,2,1,2,2,1,1,2,1,2,1,2,2,2,1,2,1,2,1,2,2,
%U A346707 1,2,1,1,2,1,2,2,2,1,2,1,2,1,2,2,1,1,2
%N A346707 "Look once to the left" sequence, omitting a(k) for each iteration k, starting with 1,2 (see example).
%C A346707 The ratio of number of 2's to number of 1's appears to converge to 1.3985918...
%e A346707 Begin with [1, 2].
%e A346707 Iteration 1: append to self, omitting term 1: [1, 2] + [2] = [1, 2, 2].
%e A346707 Iteration 2: append to self, omitting term 2: [1, 2, 2] + [1, 2] = [1, 2, 2, 1, 2].
%e A346707 Iteration 3: append to self, omitting term 3: [1, 2, 2, 1, 2] + [1, 2, 1, 2] = [1, 2, 2, 1, 2, 1, 2, 1, 2].
%t A346707 Block[{a = {1, 2}}, Do[a = Join[a, Delete[a, i]], {i, 7}]; a] (* _Michael De Vlieger_, Aug 04 2021 *)
%o A346707 (Python)
%o A346707 def sequence(iterations, start=[1,2]):
%o A346707 a = start
%o A346707 for k in range(0, iterations):
%o A346707 a = a + a[:k] + a[k+1:]
%o A346707 return a
%o A346707 (PARI) a(n) = n-=2; while(n>0, my(k=logint(n,2)); n-=1<<k; if(n<k,n--)); n+2; \\ _Kevin Ryde_, Aug 03 2021
%Y A346707 Cf. A000051, A293838.
%K A346707 nonn
%O A346707 1,2
%A A346707 _Matthew Malone_, Jul 29 2021