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 A263045 #28 Sep 08 2022 08:46:14
%S A263045 1,1,2,1,2,4,2,10,38,58,902,35578,2080262,1906407418,67898268271622,
%T A263045 141250085279900836858,269280339671247778784817867782,
%U A263045 18283668752862244903904463537467802693858298,2582569770571288306580588933602503511656010789600193877369998342
%N A263045 a(1)=a(2)=1, a(3)=2; for n>3, a(n) = (a(n-1) + a(n-2))*a(n-3) - a(n-1).
%t A263045 RecurrenceTable[{a[1]==a[2]==1,a[3]==2,a[n]==(a[n-1]+a[n-2])a[n-3]-a[n-1]}, a,{n,20}] (* _Harvey P. Dale_, Jul 23 2018 *)
%o A263045 (PARI) a(n) = if(n<4, fibonacci(n), (a(n-1)+a(n-2))*a(n-3)-a(n-1)) \\ _Altug Alkan_, Oct 08 2015
%o A263045 (Magma) I:=[1,1,2]; [n le 3 select I[n] else (Self(n-1)+ Self(n-2))*Self(n-3)-Self(n-1): n in [1..20]]; // _Vincenzo Librandi_, Oct 09 2015
%K A263045 nonn
%O A263045 1,3
%A A263045 _Gianmarco Giordano_, Oct 08 2015
%E A263045 More terms from _Altug Alkan_, Oct 08 2015