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 A074864 #14 Jun 18 2021 14:46:36
%S A074864 1,1,1,1,4,7,13,25,49,112,244,502,1051,2206,3904,7816,19243,37174,
%T A074864 66697,144349,292510,563698,1879315,3401746,6192718,15630610,33434152,
%U A074864 63708721,106919440,197375245,342218854,597294436,1527006682,3125687152
%N A074864 a(n) = a(n-1) + a(n-2) + R(a(n-3)) + R(a(n-4)) where a(1)=a(2)=a(3)=a(4)=1 and R(n) (A004086) is the reverse of n.
%H A074864 Harvey P. Dale, <a href="/A074864/b074864.txt">Table of n, a(n) for n = 1..1000</a>
%t A074864 RecurrenceTable[{a[1]==a[2]==a[3]==a[4]==1, a[n]==a[n-1]+a[n-2]+ IntegerReverse[ a[n-3]]+IntegerReverse[a[n-4]]},a,{n,40}] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Oct 10 2017 *)
%Y A074864 Cf. A000288, A074860, A074861, A074865.
%K A074864 easy,base,nonn
%O A074864 1,5
%A A074864 _Felice Russo_, Sep 11 2002
%E A074864 More terms from _Joshua Zucker_, May 08 2006
%E A074864 Definition adapted to offset by _Georg Fischer_, Jun 18 2021