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 A097334 #15 May 08 2024 05:40:49
%S A097334 1,3,3,7,19,31,59,135,259,495,1035,2071,4051,8191,16475,32679,65443,
%T A097334 131343,262059,523831,1049203,2097439,4192763,8389575,16779331,
%U A097334 33550383,67108683,134226007,268427539,536862271,1073766299,2147476455
%N A097334 a(n) = Sum_{k=0..n} C(n-k, floor(k/2))*2^k.
%H A097334 Harvey P. Dale, <a href="/A097334/b097334.txt">Table of n, a(n) for n = 0..1000</a>
%H A097334 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (1,0,4).
%F A097334 G.f. : (1+2x)/((1-2*x)*(1+x+2*x^2)); a(n)=a(n-1)+4a(n-3).
%t A097334 Table[Sum[Binomial[n-k,Floor[k/2]]2^k,{k,0,n}],{n,0,40}] (* or *) LinearRecurrence[{1,0,4},{1,3,3},40] (* _Harvey P. Dale_, May 17 2021 *)
%Y A097334 Cf. A089977, A097333, A097335.
%K A097334 easy,nonn
%O A097334 0,2
%A A097334 _Paul Barry_, Aug 05 2004