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 A178035 #11 Jun 28 2021 09:14:33 %S A178035 1,3,7,18,44,110,273,679,1687,4191,10406,25830,64097,159015,394391, %T A178035 977939,2424370,5977180,14756906 %N A178035 a(n) is the number of the two-sided n-step prudent walks ending on the top side of their box, avoiding both patterns Left^k and Down^k for k>=3. %H A178035 S. Gao and H. Niederhausen, <a href="http://math.fau.edu/Niederhausen/HTML/Papers/Sequences%20Arising%20From%20Prudent%20Self-Avoiding%20Walks-February%2001-2010.pdf">Sequences Arising From Prudent Self-Avoiding Walks</a>, 2010. %Y A178035 Cf. A177794 as the coefficients of the formal power series solution of the kernel equation of the generating function of this sequence. %K A178035 nonn,more %O A178035 0,2 %A A178035 _Shanzhen Gao_, May 17 2010