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 A110348 #4 Dec 05 2013 19:57:01 %S A110348 1,1,8,45,504,5040,86400,1247400,28828800,544864320,15850598400, %T A110348 370507737600,12996271411200,362038989312000,14867734494412800, %U A110348 480878287553664000,22629566473113600000,833522365093017600000 %N A110348 a(2) = 1 by definition; otherwise a(n) = A109347(n)/n. %F A110348 a(2n+1) = (n+1)(n+2)...(2n-1)(2n)(2n+2) ...(3n+1)(3n+2). a(2n) = (1/2)(n+1)(n+2)...(2n-2)(2n-1)(2n+1)(2n+2)...(3n-1)(3n). %e A110348 a(3) = 2*3*4/3 = 8, a(6)= 3*4*5*7*8*9/6 = 5040. %Y A110348 Cf. A110347. %K A110348 easy,nonn %O A110348 1,3 %A A110348 _Amarnath Murthy_, Jul 21 2005 %E A110348 More terms from _Joshua Zucker_, May 08 2006