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 A069073 #19 Mar 08 2022 05:09:08
%S A069073 0,9,450,3675,15876,49005,122694,266175,520200,938961,1592010,2566179,
%T A069073 3967500,5923125,8583246,12123015,16744464,22678425,30186450,39562731,
%U A069073 51136020,65271549,82372950,102884175,127291416,156125025,189961434,229425075,275190300,327983301
%N A069073 a(n) = n*(4n^2 - 1)^2.
%D A069073 L. B. W. Jolley, Summation of Series, Dover, 1961, eq. (104) on page 20.
%D A069073 Konrad Knopp, Theory and application of infinite series, Dover, p. 269.
%H A069073 Konrad Knopp, <a href="http://www.hti.umich.edu/cgi/t/text/text-idx?sid=b88432273f115fb346725f1a42422e19;c=umhistmath;idno=ACM1954.0001.001">Theorie und Anwendung der unendlichen Reihen</a>, Berlin, J. Springer, 1922. (Original German edition of "Theory and Application of Infinite Series")
%F A069073 Sum_{n>=1} 1/a(n) = 3/2 -2*log(2) = 0.113705638880109...
%F A069073 Sum_{n>=1} (-1)^(n+1)/a(n) = G + log(2) - 3/2, where G is Catalan's constant (A006752). - _Amiram Eldar_, Mar 08 2022
%t A069073 a[n_] := n*(4*n^2 - 1)^2; Array[a, 40, 0] (* _Amiram Eldar_, Mar 08 2022 *)
%Y A069073 Cf. A006752, A069075.
%K A069073 easy,nonn
%O A069073 0,2
%A A069073 _Benoit Cloitre_, Apr 05 2002