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 A127833 #2 Mar 30 2012 18:57:10 %S A127833 0,4,54,954,19116,412430,9343712,219173604,5276758498,129640779394 %N A127833 T(3n,2n), where T is the array in A127832. %e A127833 The 4 UR paths counted by a(1)=T(3,2) are RRRUU, RRURU, UURRR, URURR. These %e A127833 paths touch the line y=2x/3 only at the lattice points (0,0) and (3,2). %Y A127833 Cf. A127832. %K A127833 nonn %O A127833 0,2 %A A127833 _Clark Kimberling_, Feb 01 2007