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 A300624 #34 Nov 05 2023 17:48:24
%S A300624 0,1,22,243,1804,10165,46530,180775,614680,1871145,5188590,13286043,
%T A300624 31760676,71513949,152784282,311603535,609802800,1150082385,
%U A300624 2098144710,3714481475,6399123260,10753517061,17664712562,28418229623,44847366984,69528316025,106032285086
%N A300624 Figurate numbers based on the 11-dimensional regular convex polytope called the 11-dimensional cross-polytope, or 11-dimensional hyperoctahedron.
%C A300624 The 11-dimensional cross-polytope is represented by the Schlaefli symbol {3, 3, 3, 3, 3, 3, 3, 3, 3, 4}. It is the dual of the 11-dimensional hypercube.
%H A300624 Georg Fischer, <a href="/A300624/b300624.txt">Table of n, a(n) for n = 0..100</a> (first 61 terms from Alejandro J. Becerra Jr.)
%H A300624 <a href="/index/Rec#order_12">Index entries for linear recurrences with constant coefficients</a>, signature (12,-66,220,-495,792,-924,792,-495,220,-66,12,-1).
%F A300624 a(n) = 11-crosspolytope(n).
%F A300624 From _Colin Barker_, Aug 15 2018: (Start)
%F A300624 G.f.: x*(1 + x)^10 / (1 - x)^12.
%F A300624 a(n) = (n*(14175 + 83754*n^2 + 50270*n^4 + 7392*n^6 + 330*n^8 + 4*n^10)) / 155925.
%F A300624 (End)
%o A300624 (PARI) concat(0, Vec(x*(1 + x)^10 / (1 - x)^12 + O(x^40))) \\ _Colin Barker_, Aug 15 2018
%o A300624 (PARI) a(n) = (n*(14175 + 83754*n^2 + 50270*n^4 + 7392*n^6 + 330*n^8 + 4*n^10)) / 155925 \\ _Colin Barker_, Aug 15 2018
%o A300624 (Magma) [(n*(14175 + 83754*n^2 + 50270*n^4 + 7392*n^6 + 330*n^8 + 4*n^10)) / 155925 : n in [0..40]]; // _Wesley Ivan Hurt_, Jul 17 2020
%Y A300624 Similar sequences: A005900 (m=3), A014820(n-1) (m=4), A069038 (m=5), A069039 (m=6), A099193 (m=7), A099195 (m=8), A099196 (m=9), A099197 (m=10).
%K A300624 nonn,easy
%O A300624 0,3
%A A300624 _Alejandro J. Becerra Jr._, Aug 14 2018