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 A140132 #16 Jun 25 2024 08:31:33
%S A140132 0,1,2,6,7,8,3,4,5,9,10,11,6,7,8,3,4,5,9,10,11,6,7,8,3,4,5,9,10,11,6,
%T A140132 7,8,3,4,5,9,10,11,6,7,8,3,4,5,9,10,11,6,7,8,3,4,5,9,10,11,6,7,8,3,4,
%U A140132 5,9,10,11,6,7,8,3,4,5,9,10,11,6,7,8,3,4,5,9,10,11,6,7,8,3,4,5,9,10,11,6,7
%N A140132 a(n) = Sum_digits{a(n-1)+a(n-2)+Sum_digits[a(n-1)]+Sum_digits[a(n-2)]}, with a(0)=0 and a(1)=1.
%C A140132 After the first three terms the sequence is periodic: 6,7,8,3,4,5,9,10,11.
%p A140132 P:=proc(n) local a,i,t; t:=[0,1]; for i from 1 to n do
%p A140132 a:=t[-2]+t[-1]+convert(convert(t[-2],base,10),`+`)+convert(convert(t[-1],base,10),`+`);
%p A140132 t:=[op(t),convert(convert(a,base,10),`+`)]; od; print(op(t)); end: P(93); # _Paolo P. Lava_, Jun 25 2024
%Y A140132 Cf. A016052, A047892, A047897, A047898, A047899, A047900, A047902, A047903, A055263, A134268, A135210, A140131.
%K A140132 easy,nonn,base
%O A140132 0,3
%A A140132 _Paolo P. Lava_ and _Giorgio Balzarotti_, May 09 2008