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 A014795 #13 Mar 07 2022 03:12:50
%S A014795 1,1225,27225,207025,938961,3136441,8555625,20205025,42837025,
%T A014795 83521321,152300281,262926225,433680625,688275225,1056835081,
%U A014795 1576963521,2294889025,3266694025,4559625625,6253488241,8442118161,11234940025,14758605225,19158712225,24601608801
%N A014795 Squares of odd tetrahedral numbers.
%H A014795 <a href="/index/Rec#order_07">Index entries for linear recurrences with constant coefficients</a>, signature (7,-21,35,-35,21,-7,1).
%F A014795 From _Amiram Eldar_, Mar 07 2022: (Start)
%F A014795 a(n) = A015219(n)^2 = ((4*n+1)*(4*n+2)*(4*n+3)/6)^2.
%F A014795 Sum_{n>=0} 1/a(n) = 9*Pi*(Pi-3)/4. (End)
%t A014795 Table[((4*n+1)*(4*n+2)*(4*n+3)/6)^2, {n, 0, 40}] (* _Amiram Eldar_, Mar 07 2022 *)
%Y A014795 Cf. A000292, A015219, A014796.
%K A014795 nonn,easy
%O A014795 0,2
%A A014795 _Mohammad K. Azarian_
%E A014795 More terms from _Erich Friedman_
%E A014795 More terms from _Amiram Eldar_, Mar 07 2022