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 A175895 #7 Mar 30 2012 19:01:01
%S A175895 1,2,9,50,314,2116,14949,109246,818978,6263072,48668366,383182648,
%T A175895 3050196328,24506969724,198482172753,1618700191002,13281652367078,
%U A175895 109564878995724,908171084052990,7560049450347964,63176859344766204
%N A175895 Number of lattice paths from (0,0) to (n,n) using steps S={(k,0),(0,k),(1,1)|0<k<=2} which never go above the line y=x.
%e A175895 a(2)=9 because we can reach (2,2) in the following ways:
%e A175895 (1,0),(1,0),(0,1),(0,1)
%e A175895 (1,0),(1,0),(0,2)
%e A175895 (2,0),(0,1),(0,1)
%e A175895 (2,0),(0,2)
%e A175895 (1,0),(1,1),(0,1)
%e A175895 (1,0),(0,1),(1,1)
%e A175895 (1,1),(1,0),(0,1)
%e A175895 (1,1),(0,1),(1,0)
%e A175895 (1,1)(1,1)
%Y A175895 Cf. A006318
%K A175895 nonn
%O A175895 0,2
%A A175895 _Eric Werley_, Dec 05 2010