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 A088989 #16 Feb 16 2025 08:32:51
%S A088989 1,3,15,105,315,3465,675675,2027025,241215975,587577375,138881925,
%T A088989 1581170716125,140480936701875,219150261254925,32785574798851875,
%U A088989 106717045970262853125,1424703093055003125,33615869480632798734375
%N A088989 Denominators of coefficients of odd powers of 1/q in the solution series for Tan[x]/x=1.
%D A088989 Jerome Spanier and Keith B. Oldham, "Atlas of Functions", Hemisphere Publishing Corp., 1987, chapter 34, equation 34:7:4 at page 325.
%H A088989 Vaclav Kotesovec, <a href="/A088989/b088989.txt">Table of n, a(n) for n = 1..250</a>
%H A088989 Vaclav Kotesovec, <a href="http://oeis.org/A079330/a079330.pdf">Asymptotic of the coefficients A079330 / A088989</a>.
%H A088989 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/TancFunction.html">Tanc Function</a>.
%t A088989 Last/@Partition[CoefficientList[InverseSeries[Series[x+Cot[x], {x, 0, 50}], q], 1/q], 2]
%Y A088989 Numerators are in A079330.
%Y A088989 Cf. A224196.
%K A088989 frac,nonn
%O A088989 1,2
%A A088989 David W. Cantrell (DWCantrell(AT)sigmaxi.net), Nov 01 2003