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 A000659 #16 Apr 09 2022 11:36:51
%S A000659 0,0,1,2,5,34,17179869189
%N A000659 a(n) = 2^a(n-1) + a(n-2).
%C A000659 The next term has 5171655948 digits. - _Franklin T. Adams-Watters_, Jul 03 2009
%t A000659 Join[{a=0,b=0},Table[c=2^b+a;a=b;b=c,{n,5}]] (* _Vladimir Joseph Stephan Orlovsky_, Apr 13 2011 *)
%t A000659 nxt[{a_,b_}]:={b,2^b+a}; NestList[nxt,{0,0},6][[All,1]] (* _Harvey P. Dale_, Apr 09 2022 *)
%Y A000659 Cf. A000643.
%K A000659 nonn
%O A000659 0,4
%A A000659 _N. J. A. Sloane_