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 A072371 #4 Mar 30 2012 16:49:29 %S A072371 1,2,5,28,181,1734,18129,246072,3555945,62478090,1152624285, %T A072371 24859839060,558026987805,14266908838350,377300685054825, %U A072371 11155177913266800,339620231957641425,11399366438564677650,392645165479000867125,14749514218199731855500,567030259977151650805125 %N A072371 a(0) = 0, a(1) = 1, a(n+1) = 2*a(n) + (2*n-1)^2*a(n-1). %D A072371 A. E. Jolliffe, Continued Fractions, in Encyclopaedia Britannica, 11th ed., pp. 30-33; see p. 31. %p A072371 f := proc(n) option remember; local a,b,t1,t2,t3,i,j,k; a := 1; b := 2; if n=0 then RETURN(a) elif n=1 then RETURN(b) else RETURN(2*f(n-1)+ (2*n-3)^2*f(n-2)); fi; end; %Y A072371 Cf. A024199, A024200. %K A072371 nonn %O A072371 0,2 %A A072371 _N. J. A. Sloane_, Jul 19 2002