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 A015409 #22 Sep 08 2022 08:44:39
%S A015409 1,-40690104,2069605714586046,-100252942972187432169704,
%T A015409 4903008044094795843516454343421,
%U A015409 -239328104658006678585444195424892284704,11686690558465291130135333443500921076518590296,-570631883336806742698184435808699328319904985223284704
%N A015409 Gaussian binomial coefficient [ n,11 ] for q=-5.
%D A015409 J. Goldman and G.-C. Rota, The number of subspaces of a vector space, pp. 75-83 of W. T. Tutte, editor, Recent Progress in Combinatorics. Academic Press, NY, 1969.
%D A015409 I. P. Goulden and D. M. Jackson, Combinatorial Enumeration. Wiley, NY, 1983, p. 99.
%D A015409 M. Sved, Gaussians and binomials, Ars. Combinatoria, 17A (1984), 325-351.
%H A015409 Vincenzo Librandi, <a href="/A015409/b015409.txt">Table of n, a(n) for n = 11..140</a>
%F A015409 a(n) = Product_{i=1..11} ((-5)^(n-i+1)-1)/((-5)^i-1) (by definition). - _Vincenzo Librandi_, Nov 05 2012
%t A015409 Table[QBinomial[n, 11, -5], {n, 11, 20}] (* _Vincenzo Librandi_, Nov 05 2012 *)
%o A015409 (Sage) [gaussian_binomial(n,11,-5) for n in range(11,17)] # _Zerinvary Lajos_, May 28 2009
%o A015409 (Magma) r:=11; q:=-5; [&*[(1-q^(n-i+1))/(1-q^i): i in [1..r]]: n in [r..25]]; // _Vincenzo Librandi_, Nov 05 2012
%K A015409 sign,easy
%O A015409 11,2
%A A015409 _Olivier Gérard_